Ko, Chikusei, Ibaraki, Japan Historical Air Quality Analysis
Dive into detailed Air Quality Insights with historical data, monthly patterns, and yearly trends at your fingertips!
Good
050
Moderate
100
Poor
150
Unhealthy
200
Severe
300
Hazardous
301+
October Air Quality Analysis
Ko, Chikusei, Ibaraki, Japan
2021
2022
2024
2025
AQI
.
Days
AQI Trends: Highest and Lowest
Highest AQI recorded on
22nd Oct 2022
82AQILowest AQI recorded on
22nd Oct 2021
21AQISame Day Analysis (6th October ):
On this day, AQI across the 4 years varied significantly: 2025 ranks 1st highest AQI at 64 of Moderate air quality on the same day.
Download 2024 Annual Data
World Air Quality Report
Day & Night AQI Trend: 6th Oct - 7th Oct 2025
Ko, Chikusei, Ibaraki, Japan
AQI
Day
Night
.
5 AM6th Oct 2025
5 PM
4 AM7th Oct 2025
Day time
Avg. Highest Time
12PM6th Oct
66AQI
Avg. Lowest Time
5PM6th Oct
52AQI
Night time
Avg. Highest Time
9PM6th Oct
64AQI
Avg. Lowest Time
6PM6th Oct
53AQI
In the last 24 hours,
Ko's AQI reached its highest point of 66 at 12 PM during the Day, while the lowest point, undefined, was recorded at 4 AM during the Night between 6th Oct and 7th Oct 2025.
Day & Night AQI Trend : Sep - Oct 2025
Ko, Chikusei, Ibaraki, Japan
SepOct
07th - 08th08th - 09th09th - 10th10th - 11th11th - 12th12th - 13th13th - 14th14th - 15th15th - 16th16th - 17th17th - 18th18th - 19th19th - 20th20th - 21st21st - 22nd22nd - 23rd23rd - 24th24th - 25th25th - 26th26th - 27th27th - 28th28th - 29th29th - 30th30th - 01st01st - 02nd02nd - 03rd03rd - 04th04th - 05th05th - 06th06th - 07th07th
Day
Night
7th Sep 2025275 AMAQI
7th Sep 2025276 AMAQI
7th Sep 2025277 AMAQI
7th Sep 2025288 AMAQI
7th Sep 2025319 AMAQI
7th Sep 20252810 AMAQI
7th Sep 20253211 AMAQI
7th Sep 20253212 PMAQI
7th Sep 2025301 PMAQI
7th Sep 2025322 PMAQI
7th Sep 2025383 PMAQI
7th Sep 2025314 PMAQI
7th Sep 2025325 PMAQI
7th Sep 2025306 PMAQI
7th Sep 2025357 PMAQI
7th Sep 2025358 PMAQI
7th Sep 2025299 PMAQI
7th Sep 20252910 PMAQI
7th Sep 20252811 PMAQI
8th Sep 20252812 AMAQI
8th Sep 2025271 AMAQI
8th Sep 2025282 AMAQI
8th Sep 2025283 AMAQI
8th Sep 2025284 AMAQI
28°C24/33°C
8th Sep 2025285 AMAQI
8th Sep 2025286 AMAQI
8th Sep 2025287 AMAQI
8th Sep 2025288 AMAQI
8th Sep 2025309 AMAQI
8th Sep 20253210 AMAQI
8th Sep 20253111 AMAQI
8th Sep 20254012 PMAQI
8th Sep 2025281 PMAQI
8th Sep 2025482 PMAQI
8th Sep 2025493 PMAQI
8th Sep 2025544 PMAQI
8th Sep 2025465 PMAQI
8th Sep 2025386 PMAQI
8th Sep 2025407 PMAQI
8th Sep 2025328 PMAQI
8th Sep 2025339 PMAQI
8th Sep 20252910 PMAQI
8th Sep 20253211 PMAQI
9th Sep 20253012 AMAQI
9th Sep 2025311 AMAQI
9th Sep 2025282 AMAQI
9th Sep 2025293 AMAQI
9th Sep 2025284 AMAQI
29°C24/34°C
9th Sep 2025305 AMAQI
9th Sep 2025326 AMAQI
9th Sep 2025307 AMAQI
9th Sep 2025308 AMAQI
9th Sep 2025409 AMAQI
9th Sep 20254010 AMAQI
9th Sep 20254811 AMAQI
9th Sep 20254012 PMAQI
9th Sep 2025421 PMAQI
9th Sep 2025382 PMAQI
9th Sep 2025443 PMAQI
9th Sep 2025484 PMAQI
9th Sep 2025445 PMAQI
9th Sep 2025546 PMAQI
9th Sep 2025557 PMAQI
9th Sep 2025428 PMAQI
9th Sep 2025329 PMAQI
9th Sep 20253110 PMAQI
9th Sep 20253111 PMAQI
10th Sep 20253212 AMAQI
10th Sep 2025301 AMAQI
10th Sep 2025322 AMAQI
10th Sep 2025313 AMAQI
10th Sep 2025324 AMAQI
28°C25/33°C
10th Sep 2025335 AMAQI
10th Sep 2025346 AMAQI
10th Sep 2025337 AMAQI
10th Sep 2025338 AMAQI
10th Sep 2025449 AMAQI
10th Sep 20254410 AMAQI
10th Sep 20254811 AMAQI
10th Sep 20254212 PMAQI
10th Sep 2025451 PMAQI
10th Sep 2025322 PMAQI
10th Sep 2025403 PMAQI
10th Sep 2025344 PMAQI
10th Sep 2025275 PMAQI
10th Sep 2025306 PMAQI
10th Sep 2025277 PMAQI
10th Sep 2025318 PMAQI
10th Sep 2025329 PMAQI
10th Sep 20253010 PMAQI
10th Sep 20253011 PMAQI
11th Sep 20252912 AMAQI
11th Sep 2025341 AMAQI
11th Sep 2025342 AMAQI
11th Sep 2025333 AMAQI
11th Sep 2025344 AMAQI
26°C24/28°C
11th Sep 2025355 AMAQI
11th Sep 2025326 AMAQI
11th Sep 2025337 AMAQI
11th Sep 2025338 AMAQI
11th Sep 2025209 AMAQI
11th Sep 20252610 AMAQI
11th Sep 20251811 AMAQI
11th Sep 20252912 PMAQI
11th Sep 2025261 PMAQI
11th Sep 2025292 PMAQI
11th Sep 2025293 PMAQI
11th Sep 2025274 PMAQI
11th Sep 2025275 PMAQI
11th Sep 2025266 PMAQI
11th Sep 2025277 PMAQI
11th Sep 2025298 PMAQI
11th Sep 2025299 PMAQI
11th Sep 20253010 PMAQI
11th Sep 20252811 PMAQI
12th Sep 20253112 AMAQI
12th Sep 2025331 AMAQI
12th Sep 2025342 AMAQI
12th Sep 2025353 AMAQI
12th Sep 2025344 AMAQI
24°C23/26°C
12th Sep 2025325 AMAQI
12th Sep 2025326 AMAQI
12th Sep 2025327 AMAQI
12th Sep 2025318 AMAQI
12th Sep 2025239 AMAQI
12th Sep 20252810 AMAQI
12th Sep 20252211 AMAQI
12th Sep 20252512 PMAQI
12th Sep 2025261 PMAQI
12th Sep 2025312 PMAQI
12th Sep 2025283 PMAQI
12th Sep 2025304 PMAQI
12th Sep 2025275 PMAQI
12th Sep 2025306 PMAQI
12th Sep 2025307 PMAQI
12th Sep 2025278 PMAQI
12th Sep 2025269 PMAQI
12th Sep 20252610 PMAQI
12th Sep 20252711 PMAQI
13th Sep 20252812 AMAQI
13th Sep 2025331 AMAQI
13th Sep 2025342 AMAQI
13th Sep 2025343 AMAQI
13th Sep 2025344 AMAQI
24°C22/26°C
13th Sep 2025335 AMAQI
13th Sep 2025346 AMAQI
13th Sep 2025337 AMAQI
13th Sep 2025348 AMAQI
13th Sep 2025189 AMAQI
13th Sep 20251410 AMAQI
13th Sep 20252011 AMAQI
13th Sep 20252312 PMAQI
13th Sep 2025221 PMAQI
13th Sep 2025192 PMAQI
13th Sep 2025213 PMAQI
13th Sep 2025224 PMAQI
13th Sep 2025205 PMAQI
13th Sep 2025156 PMAQI
13th Sep 2025197 PMAQI
13th Sep 2025248 PMAQI
13th Sep 2025279 PMAQI
13th Sep 20252510 PMAQI
13th Sep 20252611 PMAQI
14th Sep 20253212 AMAQI
14th Sep 2025361 AMAQI
14th Sep 2025352 AMAQI
14th Sep 2025353 AMAQI
14th Sep 2025334 AMAQI
25°C22/29°C
14th Sep 2025345 AMAQI
14th Sep 2025326 AMAQI
14th Sep 2025347 AMAQI
14th Sep 2025358 AMAQI
14th Sep 2025239 AMAQI
14th Sep 20252210 AMAQI
14th Sep 20252511 AMAQI
14th Sep 20251812 PMAQI
14th Sep 2025211 PMAQI
14th Sep 2025202 PMAQI
14th Sep 2025243 PMAQI
14th Sep 2025284 PMAQI
14th Sep 2025305 PMAQI
14th Sep 2025386 PMAQI
14th Sep 2025377 PMAQI
14th Sep 2025348 PMAQI
14th Sep 2025349 PMAQI
14th Sep 20253410 PMAQI
14th Sep 20253411 PMAQI
15th Sep 20253212 AMAQI
15th Sep 2025331 AMAQI
15th Sep 2025342 AMAQI
15th Sep 2025343 AMAQI
15th Sep 2025334 AMAQI
27°C24/32°C
15th Sep 2025325 AMAQI
15th Sep 2025346 AMAQI
15th Sep 2025337 AMAQI
15th Sep 2025338 AMAQI
15th Sep 2025349 AMAQI
15th Sep 20253010 AMAQI
15th Sep 20252911 AMAQI
15th Sep 20253212 PMAQI
15th Sep 2025281 PMAQI
15th Sep 2025252 PMAQI
15th Sep 2025253 PMAQI
15th Sep 2025284 PMAQI
15th Sep 2025325 PMAQI
15th Sep 2025346 PMAQI
15th Sep 2025387 PMAQI
15th Sep 2025368 PMAQI
15th Sep 2025359 PMAQI
15th Sep 20253210 PMAQI
15th Sep 20253311 PMAQI
16th Sep 20253012 AMAQI
16th Sep 2025331 AMAQI
16th Sep 2025342 AMAQI
16th Sep 2025343 AMAQI
16th Sep 2025334 AMAQI
27°C24/32°C
16th Sep 2025325 AMAQI
16th Sep 2025326 AMAQI
16th Sep 2025327 AMAQI
16th Sep 2025338 AMAQI
16th Sep 2025399 AMAQI
16th Sep 20254210 AMAQI
16th Sep 20254811 AMAQI
16th Sep 20255412 PMAQI
16th Sep 2025541 PMAQI
16th Sep 2025562 PMAQI
16th Sep 2025623 PMAQI
16th Sep 2025604 PMAQI
16th Sep 2025615 PMAQI
16th Sep 2025596 PMAQI
16th Sep 2025577 PMAQI
16th Sep 2025398 PMAQI
16th Sep 2025369 PMAQI
16th Sep 20253210 PMAQI
16th Sep 20253111 PMAQI
17th Sep 20253212 AMAQI
17th Sep 2025331 AMAQI
17th Sep 2025322 AMAQI
17th Sep 2025333 AMAQI
17th Sep 2025354 AMAQI
28°C25/33°C
17th Sep 2025375 AMAQI
17th Sep 2025386 AMAQI
17th Sep 2025377 AMAQI
17th Sep 2025388 AMAQI
17th Sep 2025469 AMAQI
17th Sep 20255210 AMAQI
17th Sep 20255511 AMAQI
17th Sep 20255712 PMAQI
17th Sep 2025581 PMAQI
17th Sep 2025602 PMAQI
17th Sep 2025563 PMAQI
17th Sep 2025504 PMAQI
17th Sep 2025545 PMAQI
17th Sep 2025436 PMAQI
17th Sep 2025567 PMAQI
17th Sep 2025428 PMAQI
17th Sep 2025539 PMAQI
17th Sep 20255610 PMAQI
17th Sep 20255511 PMAQI
18th Sep 20255112 AMAQI
18th Sep 2025341 AMAQI
18th Sep 2025342 AMAQI
18th Sep 2025343 AMAQI
18th Sep 2025374 AMAQI
30°C25/35°C
18th Sep 2025405 AMAQI
18th Sep 2025406 AMAQI
18th Sep 2025397 AMAQI
18th Sep 2025408 AMAQI
18th Sep 2025549 AMAQI
18th Sep 20256010 AMAQI
18th Sep 20256211 AMAQI
18th Sep 20256512 PMAQI
18th Sep 2025601 PMAQI
18th Sep 2025602 PMAQI
18th Sep 2025553 PMAQI
18th Sep 2025514 PMAQI
18th Sep 2025325 PMAQI
18th Sep 2025246 PMAQI
18th Sep 2025237 PMAQI
18th Sep 2025268 PMAQI
18th Sep 2025319 PMAQI
18th Sep 20253010 PMAQI
18th Sep 20252911 PMAQI
19th Sep 20253012 AMAQI
19th Sep 2025351 AMAQI
19th Sep 2025382 AMAQI
19th Sep 2025363 AMAQI
19th Sep 2025404 AMAQI
28°C22/36°C
19th Sep 2025485 AMAQI
19th Sep 2025486 AMAQI
19th Sep 2025487 AMAQI
19th Sep 2025488 AMAQI
19th Sep 2025289 AMAQI
19th Sep 20251810 AMAQI
19th Sep 20251911 AMAQI
19th Sep 20252012 PMAQI
19th Sep 2025201 PMAQI
19th Sep 2025212 PMAQI
19th Sep 2025223 PMAQI
19th Sep 2025224 PMAQI
19th Sep 2025225 PMAQI
19th Sep 2025246 PMAQI
19th Sep 2025237 PMAQI
19th Sep 2025288 PMAQI
19th Sep 2025349 PMAQI
19th Sep 20253610 PMAQI
19th Sep 20253211 PMAQI
20th Sep 20253212 AMAQI
20th Sep 2025341 AMAQI
20th Sep 2025372 AMAQI
20th Sep 2025383 AMAQI
20th Sep 2025374 AMAQI
22°C20/24°C
20th Sep 2025345 AMAQI
20th Sep 2025346 AMAQI
20th Sep 2025347 AMAQI
20th Sep 2025348 AMAQI
20th Sep 2025249 AMAQI
20th Sep 20252110 AMAQI
20th Sep 20252011 AMAQI
20th Sep 20251912 PMAQI
20th Sep 2025161 PMAQI
20th Sep 2025192 PMAQI
20th Sep 2025203 PMAQI
20th Sep 2025204 PMAQI
20th Sep 2025215 PMAQI
20th Sep 2025236 PMAQI
20th Sep 2025247 PMAQI
20th Sep 2025288 PMAQI
20th Sep 2025309 PMAQI
20th Sep 20253010 PMAQI
20th Sep 20252811 PMAQI
21st Sep 20253012 AMAQI
21st Sep 2025331 AMAQI
21st Sep 2025342 AMAQI
21st Sep 2025343 AMAQI
21st Sep 2025334 AMAQI
23°C21/25°C
21st Sep 2025325 AMAQI
21st Sep 2025336 AMAQI
21st Sep 2025327 AMAQI
21st Sep 2025328 AMAQI
21st Sep 2025289 AMAQI
21st Sep 20252410 AMAQI
21st Sep 20251911 AMAQI
21st Sep 20251812 PMAQI
21st Sep 2025191 PMAQI
21st Sep 2025162 PMAQI
21st Sep 2025183 PMAQI
21st Sep 2025174 PMAQI
21st Sep 2025185 PMAQI
21st Sep 2025186 PMAQI
21st Sep 2025187 PMAQI
21st Sep 2025228 PMAQI
21st Sep 2025269 PMAQI
21st Sep 20252810 PMAQI
21st Sep 20252711 PMAQI
22nd Sep 20252612 AMAQI
22nd Sep 2025311 AMAQI
22nd Sep 2025332 AMAQI
22nd Sep 2025333 AMAQI
22nd Sep 2025324 AMAQI
24°C21/30°C
22nd Sep 2025315 AMAQI
22nd Sep 2025306 AMAQI
22nd Sep 2025307 AMAQI
22nd Sep 2025318 AMAQI
22nd Sep 2025209 AMAQI
22nd Sep 20252010 AMAQI
22nd Sep 20252011 AMAQI
22nd Sep 20252212 PMAQI
22nd Sep 2025221 PMAQI
22nd Sep 2025222 PMAQI
22nd Sep 2025223 PMAQI
22nd Sep 2025234 PMAQI
22nd Sep 2025225 PMAQI
22nd Sep 2025186 PMAQI
22nd Sep 2025187 PMAQI
22nd Sep 2025228 PMAQI
22nd Sep 2025269 PMAQI
22nd Sep 20252410 PMAQI
22nd Sep 20252511 PMAQI
23rd Sep 20252612 AMAQI
23rd Sep 2025271 AMAQI
23rd Sep 2025302 AMAQI
23rd Sep 2025303 AMAQI
23rd Sep 2025304 AMAQI
22°C20/26°C
23rd Sep 2025295 AMAQI
23rd Sep 2025286 AMAQI
23rd Sep 2025297 AMAQI
23rd Sep 2025298 AMAQI
23rd Sep 2025269 AMAQI
23rd Sep 20252210 AMAQI
23rd Sep 20252011 AMAQI
23rd Sep 20251812 PMAQI
23rd Sep 2025191 PMAQI
23rd Sep 2025192 PMAQI
23rd Sep 2025203 PMAQI
23rd Sep 2025214 PMAQI
23rd Sep 2025245 PMAQI
23rd Sep 2025226 PMAQI
23rd Sep 2025207 PMAQI
23rd Sep 2025238 PMAQI
23rd Sep 2025269 PMAQI
23rd Sep 20252610 PMAQI
23rd Sep 20252611 PMAQI
24th Sep 20252512 AMAQI
24th Sep 2025261 AMAQI
24th Sep 2025282 AMAQI
24th Sep 2025293 AMAQI
24th Sep 2025284 AMAQI
21°C18/25°C
24th Sep 2025275 AMAQI
24th Sep 2025276 AMAQI
24th Sep 2025277 AMAQI
24th Sep 2025278 AMAQI
24th Sep 2025249 AMAQI
24th Sep 20252610 AMAQI
24th Sep 20252311 AMAQI
24th Sep 20252212 PMAQI
24th Sep 2025251 PMAQI
24th Sep 2025262 PMAQI
24th Sep 2025233 PMAQI
24th Sep 2025264 PMAQI
24th Sep 2025235 PMAQI
24th Sep 2025246 PMAQI
24th Sep 2025237 PMAQI
24th Sep 2025248 PMAQI
24th Sep 2025279 PMAQI
24th Sep 20252710 PMAQI
24th Sep 20252611 PMAQI
25th Sep 20252512 AMAQI
25th Sep 2025271 AMAQI
25th Sep 2025272 AMAQI
25th Sep 2025273 AMAQI
25th Sep 2025274 AMAQI
21°C17/26°C
25th Sep 2025265 AMAQI
25th Sep 2025266 AMAQI
25th Sep 2025267 AMAQI
25th Sep 2025268 AMAQI
25th Sep 2025279 AMAQI
25th Sep 20252610 AMAQI
25th Sep 20252811 AMAQI
25th Sep 20253112 PMAQI
25th Sep 2025341 PMAQI
25th Sep 2025462 PMAQI
25th Sep 2025673 PMAQI
25th Sep 2025724 PMAQI
25th Sep 2025695 PMAQI
25th Sep 2025616 PMAQI
25th Sep 2025577 PMAQI
25th Sep 2025598 PMAQI
25th Sep 2025609 PMAQI
25th Sep 20255810 PMAQI
25th Sep 20255911 PMAQI
26th Sep 20255512 AMAQI
26th Sep 2025551 AMAQI
26th Sep 2025552 AMAQI
26th Sep 2025553 AMAQI
26th Sep 2025564 AMAQI
24°C19/29°C
26th Sep 2025565 AMAQI
26th Sep 2025576 AMAQI
26th Sep 2025587 AMAQI
26th Sep 2025568 AMAQI
26th Sep 2025589 AMAQI
26th Sep 20255810 AMAQI
26th Sep 20255511 AMAQI
26th Sep 20254812 PMAQI
26th Sep 2025451 PMAQI
26th Sep 2025492 PMAQI
26th Sep 2025513 PMAQI
26th Sep 2025524 PMAQI
26th Sep 2025485 PMAQI
26th Sep 2025526 PMAQI
26th Sep 2025577 PMAQI
26th Sep 2025578 PMAQI
26th Sep 2025569 PMAQI
26th Sep 20255010 PMAQI
26th Sep 20255311 PMAQI
27th Sep 20255412 AMAQI
27th Sep 2025451 AMAQI
27th Sep 2025392 AMAQI
27th Sep 2025343 AMAQI
27th Sep 2025354 AMAQI
26°C22/32°C
27th Sep 2025405 AMAQI
27th Sep 2025406 AMAQI
27th Sep 2025477 AMAQI
27th Sep 2025508 AMAQI
27th Sep 2025429 AMAQI
27th Sep 20253910 AMAQI
27th Sep 20254311 AMAQI
27th Sep 20254912 PMAQI
27th Sep 2025461 PMAQI
27th Sep 2025522 PMAQI
27th Sep 2025553 PMAQI
27th Sep 2025544 PMAQI
27th Sep 2025545 PMAQI
27th Sep 2025546 PMAQI
27th Sep 2025537 PMAQI
27th Sep 2025518 PMAQI
27th Sep 2025469 PMAQI
27th Sep 20254710 PMAQI
27th Sep 20254611 PMAQI
28th Sep 20254912 AMAQI
28th Sep 2025481 AMAQI
28th Sep 2025412 AMAQI
28th Sep 2025463 AMAQI
28th Sep 2025524 AMAQI
24°C22/28°C
28th Sep 2025515 AMAQI
28th Sep 2025466 AMAQI
28th Sep 2025447 AMAQI
28th Sep 2025498 AMAQI
28th Sep 2025509 AMAQI
28th Sep 20255010 AMAQI
28th Sep 20254611 AMAQI
28th Sep 20255112 PMAQI
28th Sep 2025531 PMAQI
28th Sep 2025512 PMAQI
28th Sep 2025503 PMAQI
28th Sep 2025524 PMAQI
28th Sep 2025525 PMAQI
28th Sep 2025526 PMAQI
28th Sep 2025527 PMAQI
28th Sep 2025458 PMAQI
28th Sep 2025489 PMAQI
28th Sep 20254610 PMAQI
28th Sep 20254811 PMAQI
29th Sep 20254612 AMAQI
29th Sep 2025461 AMAQI
29th Sep 2025512 AMAQI
29th Sep 2025553 AMAQI
29th Sep 2025554 AMAQI
23°C21/26°C
29th Sep 2025565 AMAQI
29th Sep 2025566 AMAQI
29th Sep 2025557 AMAQI
29th Sep 2025538 AMAQI
29th Sep 2025539 AMAQI
29th Sep 20255510 AMAQI
29th Sep 20255511 AMAQI
29th Sep 20257812 PMAQI
29th Sep 2025721 PMAQI
29th Sep 2025712 PMAQI
29th Sep 2025803 PMAQI
29th Sep 2025764 PMAQI
29th Sep 2025725 PMAQI
29th Sep 2025696 PMAQI
29th Sep 2025757 PMAQI
29th Sep 2025758 PMAQI
29th Sep 2025639 PMAQI
29th Sep 20255010 PMAQI
29th Sep 20254711 PMAQI
30th Sep 20254512 AMAQI
30th Sep 2025391 AMAQI
30th Sep 2025402 AMAQI
30th Sep 2025423 AMAQI
30th Sep 2025484 AMAQI
26°C22/33°C
30th Sep 2025375 AMAQI
30th Sep 2025426 AMAQI
30th Sep 2025347 AMAQI
30th Sep 2025338 AMAQI
30th Sep 2025429 AMAQI
30th Sep 20254410 AMAQI
30th Sep 20254711 AMAQI
30th Sep 20254712 PMAQI
30th Sep 2025501 PMAQI
30th Sep 2025552 PMAQI
30th Sep 2025523 PMAQI
30th Sep 2025544 PMAQI
30th Sep 2025535 PMAQI
30th Sep 2025686 PMAQI
30th Sep 2025707 PMAQI
30th Sep 2025848 PMAQI
30th Sep 2025669 PMAQI
30th Sep 20256310 PMAQI
30th Sep 20256811 PMAQI
1st Oct 20255312 AMAQI
1st Oct 2025531 AMAQI
1st Oct 2025552 AMAQI
1st Oct 2025523 AMAQI
1st Oct 2025524 AMAQI
23°C21/26°C
1st Oct 2025545 AMAQI
1st Oct 2025566 AMAQI
1st Oct 2025557 AMAQI
1st Oct 2025528 AMAQI
1st Oct 2025509 AMAQI
1st Oct 20255310 AMAQI
1st Oct 20255311 AMAQI
1st Oct 20255612 PMAQI
1st Oct 2025531 PMAQI
1st Oct 2025532 PMAQI
1st Oct 2025463 PMAQI
1st Oct 2025444 PMAQI
1st Oct 2025445 PMAQI
1st Oct 2025386 PMAQI
1st Oct 2025357 PMAQI
1st Oct 2025338 PMAQI
1st Oct 2025359 PMAQI
1st Oct 20253510 PMAQI
1st Oct 20253411 PMAQI
2nd Oct 20253212 AMAQI
2nd Oct 2025431 AMAQI
2nd Oct 2025422 AMAQI
2nd Oct 2025393 AMAQI
2nd Oct 2025424 AMAQI
20°C19/20°C
2nd Oct 2025415 AMAQI
2nd Oct 2025416 AMAQI
2nd Oct 2025487 AMAQI
2nd Oct 2025478 AMAQI
2nd Oct 2025489 AMAQI
2nd Oct 20255410 AMAQI
2nd Oct 20255311 AMAQI
2nd Oct 20255512 PMAQI
2nd Oct 2025641 PMAQI
2nd Oct 2025632 PMAQI
2nd Oct 2025633 PMAQI
2nd Oct 2025624 PMAQI
2nd Oct 2025565 PMAQI
2nd Oct 2025576 PMAQI
2nd Oct 2025517 PMAQI
2nd Oct 2025518 PMAQI
2nd Oct 2025539 PMAQI
2nd Oct 20255610 PMAQI
2nd Oct 20255811 PMAQI
3rd Oct 20255712 AMAQI
3rd Oct 2025591 AMAQI
3rd Oct 2025572 AMAQI
3rd Oct 2025533 AMAQI
3rd Oct 2025524 AMAQI
22°C18/27°C
3rd Oct 2025515 AMAQI
3rd Oct 2025496 AMAQI
3rd Oct 2025397 AMAQI
3rd Oct 2025468 AMAQI
3rd Oct 2025529 AMAQI
3rd Oct 20255310 AMAQI
3rd Oct 20254711 AMAQI
3rd Oct 20255212 PMAQI
3rd Oct 2025501 PMAQI
3rd Oct 2025532 PMAQI
3rd Oct 2025543 PMAQI
3rd Oct 2025524 PMAQI
3rd Oct 2025485 PMAQI
3rd Oct 2025546 PMAQI
3rd Oct 2025557 PMAQI
3rd Oct 2025478 PMAQI
3rd Oct 2025679 PMAQI
3rd Oct 20257010 PMAQI
3rd Oct 20256911 PMAQI
4th Oct 20257112 AMAQI
4th Oct 2025691 AMAQI
4th Oct 2025682 AMAQI
4th Oct 2025663 AMAQI
4th Oct 2025664 AMAQI
22°C18/26°C
4th Oct 2025645 AMAQI
4th Oct 2025636 AMAQI
4th Oct 2025637 AMAQI
4th Oct 2025678 AMAQI
4th Oct 2025649 AMAQI
4th Oct 20256510 AMAQI
4th Oct 20256511 AMAQI
4th Oct 20256412 PMAQI
4th Oct 2025641 PMAQI
4th Oct 2025642 PMAQI
4th Oct 2025633 PMAQI
4th Oct 2025634 PMAQI
4th Oct 2025605 PMAQI
4th Oct 2025606 PMAQI
4th Oct 2025627 PMAQI
4th Oct 2025588 PMAQI
4th Oct 2025569 PMAQI
4th Oct 20255510 PMAQI
4th Oct 20255611 PMAQI
5th Oct 20255612 AMAQI
5th Oct 2025551 AMAQI
5th Oct 2025562 AMAQI
5th Oct 2025523 AMAQI
5th Oct 2025514 AMAQI
22°C20/24°C
5th Oct 2025525 AMAQI
5th Oct 2025526 AMAQI
5th Oct 2025507 AMAQI
5th Oct 2025498 AMAQI
5th Oct 2025549 AMAQI
5th Oct 20255710 AMAQI
5th Oct 20255611 AMAQI
5th Oct 20255512 PMAQI
5th Oct 2025551 PMAQI
5th Oct 2025572 PMAQI
5th Oct 2025593 PMAQI
5th Oct 2025614 PMAQI
5th Oct 2025615 PMAQI
5th Oct 2025676 PMAQI
5th Oct 2025667 PMAQI
5th Oct 2025638 PMAQI
5th Oct 2025659 PMAQI
5th Oct 20256710 PMAQI
5th Oct 20257111 PMAQI
6th Oct 20256812 AMAQI
6th Oct 2025611 AMAQI
6th Oct 2025602 AMAQI
6th Oct 2025613 AMAQI
6th Oct 2025634 AMAQI
24°C20/27°C
6th Oct 2025635 AMAQI
6th Oct 2025616 AMAQI
6th Oct 2025577 AMAQI
6th Oct 2025598 AMAQI
6th Oct 2025599 AMAQI
6th Oct 20256010 AMAQI
6th Oct 20256311 AMAQI
6th Oct 20256612 PMAQI
6th Oct 2025621 PMAQI
6th Oct 2025622 PMAQI
6th Oct 2025623 PMAQI
6th Oct 2025584 PMAQI
6th Oct 2025525 PMAQI
6th Oct 2025536 PMAQI
6th Oct 2025587 PMAQI
6th Oct 2025628 PMAQI
6th Oct 2025649 PMAQI
6th Oct 20256210 PMAQI
6th Oct 20255711 PMAQI
7th Oct 20255912 AMAQI
7th Oct 2025591 AMAQI
7th Oct 2025582 AMAQI
23°C20/28°C
5 AM
11 AM
5 PM
7th Oct 2025528 PMAQI
11 PM
4 AM
--°C/°C
Day time
Avg. Highest Time
2 PM - 4 PM
43AQI
3 hours / Day
90 hours / Month
Avg. Lowest Time
5 AM - 11 AM
39AQI
7 hours / Day
210 hours / Month
In the last 30 days, during the daytime, the highest AQI was between 2 PM to 4 PM (Avg. 43), while the lowest AQI was between 5 AM to 11 AM (Avg. 39).
Night time
Avg. Highest Time
12 AM - 9 PM
40AQI
9 hours / Day
270 hours / Month
Avg. Lowest Time
12 AM - 11 PM
40AQI
11 hours / Day
330 hours / Month
In the last 30 days, during the daytime, the highest AQI was between 12 AM to 9 PM (Avg. 40), while the lowest AQI was between 12 AM to 11 PM (Avg. 40).
2025 Days Vs Air Quality
Ko, Chikusei, Ibaraki, Japan
2025
89%
249
11%
30
Total number of days with different AQI categories in last 280 days in 2025 (85 days remaining)
Good
249 DaysModerate
30 DaysPoor
0 DaysUnhealthy
0 DaysSevere
0 DaysHazardous
0 DaysUnder WHO’s Safe Air Quality Limits: 89%
Health Risk Level:
Low
In 2025, 89% of 280 days were within WHO’s safe air quality limits. The risk of health issues is Low, but the long-term effects, especially on vulnerable individuals, remain uncertain.
Annual Air Quality Insights
Ko, Chikusei, Ibaraki, Japan
AQI levels in 2025
AQI
PM2.5
PM10
CO
SO2
NO2
O3
Sun.Mon.Tue.Wed.Thu.Fri.Sat.
Jan.
Feb.
Mar.
Apr.
May
Jun.
Jul.
Aug.
Sep.
Oct.
Nov.
Dec.
-1th undefined 2025
-1th undefined 2025
-1th undefined 2025
1st January 2025
32AQI
32AQI
2nd January 2025
35AQI
35AQI
3rd January 2025
26AQI
26AQI
4th January 2025
27AQI
27AQI
5th January 2025
34AQI
34AQI
6th January 2025
57AQI
57AQI
7th January 2025
35AQI
35AQI
8th January 2025
37AQI
37AQI
9th January 2025
28AQI
28AQI
10th January 2025
30AQI
30AQI
11th January 2025
28AQI
28AQI
12th January 2025
38AQI
38AQI
13th January 2025
30AQI
30AQI
14th January 2025
39AQI
39AQI
15th January 2025
35AQI
35AQI
16th January 2025
34AQI
34AQI
17th January 2025
31AQI
31AQI
18th January 2025
35AQI
35AQI
19th January 2025
59AQI
59AQI
20th January 2025
42AQI
42AQI
21st January 2025
48AQI
48AQI
22nd January 2025
40AQI
40AQI
23rd January 2025
48AQI
48AQI
24th January 2025
46AQI
46AQI
25th January 2025
39AQI
39AQI
26th January 2025
35AQI
35AQI
27th January 2025
36AQI
36AQI
28th January 2025
40AQI
40AQI
29th January 2025
31AQI
31AQI
30th January 2025
32AQI
32AQI
31st January 2025
29AQI
29AQI
1st February 2025
35AQI
35AQI
2nd February 2025
34AQI
34AQI
3rd February 2025
39AQI
39AQI
4th February 2025
31AQI
31AQI
5th February 2025
34AQI
34AQI
6th February 2025
28AQI
28AQI
7th February 2025
30AQI
30AQI
8th February 2025
30AQI
30AQI
9th February 2025
30AQI
30AQI
10th February 2025
30AQI
30AQI
11th February 2025
30AQI
30AQI
12th February 2025
40AQI
40AQI
13th February 2025
38AQI
38AQI
14th February 2025
34AQI
34AQI
15th February 2025
33AQI
33AQI
16th February 2025
38AQI
38AQI
17th February 2025
36AQI
36AQI
18th February 2025
32AQI
32AQI
19th February 2025
31AQI
31AQI
20th February 2025
31AQI
31AQI
21st February 2025
31AQI
31AQI
22nd February 2025
31AQI
31AQI
23rd February 2025
32AQI
32AQI
24th February 2025
32AQI
32AQI
25th February 2025
34AQI
34AQI
26th February 2025
38AQI
38AQI
27th February 2025
40AQI
40AQI
28th February 2025
50AQI
50AQI
1st March 2025
49AQI
49AQI
2nd March 2025
59AQI
59AQI
3rd March 2025
39AQI
39AQI
4th March 2025
38AQI
38AQI
5th March 2025
26AQI
26AQI
6th March 2025
33AQI
33AQI
7th March 2025
31AQI
31AQI
8th March 2025
37AQI
37AQI
9th March 2025
35AQI
35AQI
10th March 2025
37AQI
37AQI
11th March 2025
45AQI
45AQI
12th March 2025
47AQI
47AQI
13th March 2025
45AQI
45AQI
14th March 2025
37AQI
37AQI
15th March 2025
39AQI
39AQI
16th March 2025
24AQI
24AQI
17th March 2025
23AQI
23AQI
18th March 2025
24AQI
24AQI
19th March 2025
19AQI
19AQI
20th March 2025
26AQI
26AQI
21st March 2025
40AQI
40AQI
22nd March 2025
49AQI
49AQI
23rd March 2025
51AQI
51AQI
24th March 2025
50AQI
50AQI
25th March 2025
67AQI
67AQI
26th March 2025
63AQI
63AQI
27th March 2025
66AQI
66AQI
28th March 2025
49AQI
49AQI
29th March 2025
38AQI
38AQI
30th March 2025
33AQI
33AQI
31st March 2025
31AQI
31AQI
1st April 2025
26AQI
26AQI
2nd April 2025
22AQI
22AQI
3rd April 2025
20AQI
20AQI
4th April 2025
24AQI
24AQI
5th April 2025
24AQI
24AQI
6th April 2025
20AQI
20AQI
7th April 2025
25AQI
25AQI
8th April 2025
32AQI
32AQI
9th April 2025
23AQI
23AQI
10th April 2025
39AQI
39AQI
11th April 2025
35AQI
35AQI
12th April 2025
29AQI
29AQI
13th April 2025
23AQI
23AQI
14th April 2025
26AQI
26AQI
15th April 2025
22AQI
22AQI
16th April 2025
20AQI
20AQI
17th April 2025
37AQI
37AQI
18th April 2025
46AQI
46AQI
19th April 2025
55AQI
55AQI
20th April 2025
45AQI
45AQI
21st April 2025
38AQI
38AQI
22nd April 2025
42AQI
42AQI
23rd April 2025
23AQI
23AQI
24th April 2025
33AQI
33AQI
25th April 2025
29AQI
29AQI
26th April 2025
40AQI
40AQI
27th April 2025
39AQI
39AQI
28th April 2025
44AQI
44AQI
29th April 2025
27AQI
27AQI
30th April 2025
34AQI
34AQI
1st May 2025
30AQI
30AQI
2nd May 2025
25AQI
25AQI
3rd May 2025
27AQI
27AQI
4th May 2025
30AQI
30AQI
5th May 2025
28AQI
28AQI
6th May 2025
22AQI
22AQI
7th May 2025
21AQI
21AQI
8th May 2025
24AQI
24AQI
9th May 2025
25AQI
25AQI
10th May 2025
19AQI
19AQI
11th May 2025
22AQI
22AQI
12th May 2025
18AQI
18AQI
13th May 2025
30AQI
30AQI
14th May 2025
32AQI
32AQI
15th May 2025
34AQI
34AQI
16th May 2025
40AQI
40AQI
17th May 2025
24AQI
24AQI
18th May 2025
40AQI
40AQI
19th May 2025
34AQI
34AQI
20th May 2025
52AQI
52AQI
21st May 2025
48AQI
48AQI
22nd May 2025
44AQI
44AQI
23rd May 2025
42AQI
42AQI
24th May 2025
35AQI
35AQI
25th May 2025
27AQI
27AQI
26th May 2025
26AQI
26AQI
27th May 2025
23AQI
23AQI
28th May 2025
22AQI
22AQI
29th May 2025
25AQI
25AQI
30th May 2025
20AQI
20AQI
31st May 2025
16AQI
16AQI
1st June 2025
18AQI
18AQI
2nd June 2025
27AQI
27AQI
3rd June 2025
28AQI
28AQI
4th June 2025
24AQI
24AQI
5th June 2025
31AQI
31AQI
6th June 2025
42AQI
42AQI
7th June 2025
46AQI
46AQI
8th June 2025
55AQI
55AQI
9th June 2025
45AQI
45AQI
10th June 2025
35AQI
35AQI
11th June 2025
30AQI
30AQI
12th June 2025
38AQI
38AQI
13th June 2025
31AQI
31AQI
14th June 2025
31AQI
31AQI
15th June 2025
29AQI
29AQI
16th June 2025
33AQI
33AQI
17th June 2025
40AQI
40AQI
18th June 2025
40AQI
40AQI
19th June 2025
41AQI
41AQI
20th June 2025
39AQI
39AQI
21st June 2025
35AQI
35AQI
22nd June 2025
30AQI
30AQI
23rd June 2025
30AQI
30AQI
24th June 2025
32AQI
32AQI
25th June 2025
25AQI
25AQI
26th June 2025
28AQI
28AQI
27th June 2025
33AQI
33AQI
28th June 2025
34AQI
34AQI
29th June 2025
41AQI
41AQI
30th June 2025
45AQI
45AQI
1st July 2025
44AQI
44AQI
2nd July 2025
47AQI
47AQI
3rd July 2025
48AQI
48AQI
4th July 2025
50AQI
50AQI
5th July 2025
53AQI
53AQI
6th July 2025
62AQI
62AQI
7th July 2025
76AQI
76AQI
8th July 2025
77AQI
77AQI
9th July 2025
80AQI
80AQI
10th July 2025
59AQI
59AQI
11th July 2025
47AQI
47AQI
12th July 2025
49AQI
49AQI
13th July 2025
51AQI
51AQI
14th July 2025
38AQI
38AQI
15th July 2025
38AQI
38AQI
16th July 2025
40AQI
40AQI
17th July 2025
40AQI
40AQI
18th July 2025
37AQI
37AQI
19th July 2025
36AQI
36AQI
20th July 2025
37AQI
37AQI
21st July 2025
43AQI
43AQI
22nd July 2025
44AQI
44AQI
23rd July 2025
46AQI
46AQI
24th July 2025
48AQI
48AQI
25th July 2025
48AQI
48AQI
26th July 2025
48AQI
48AQI
27th July 2025
45AQI
45AQI
28th July 2025
45AQI
45AQI
29th July 2025
43AQI
43AQI
30th July 2025
36AQI
36AQI
31st July 2025
36AQI
36AQI
1st August 2025
34AQI
34AQI
2nd August 2025
39AQI
39AQI
3rd August 2025
43AQI
43AQI
4th August 2025
56AQI
56AQI
5th August 2025
49AQI
49AQI
6th August 2025
47AQI
47AQI
7th August 2025
40AQI
40AQI
8th August 2025
39AQI
39AQI
9th August 2025
37AQI
37AQI
10th August 2025
35AQI
35AQI
11th August 2025
35AQI
35AQI
12th August 2025
32AQI
32AQI
13th August 2025
31AQI
31AQI
14th August 2025
31AQI
31AQI
15th August 2025
32AQI
32AQI
16th August 2025
33AQI
33AQI
17th August 2025
38AQI
38AQI
18th August 2025
41AQI
41AQI
19th August 2025
42AQI
42AQI
20th August 2025
48AQI
48AQI
21st August 2025
46AQI
46AQI
22nd August 2025
47AQI
47AQI
23rd August 2025
48AQI
48AQI
24th August 2025
53AQI
53AQI
25th August 2025
53AQI
53AQI
26th August 2025
53AQI
53AQI
27th August 2025
48AQI
48AQI
28th August 2025
45AQI
45AQI
29th August 2025
48AQI
48AQI
30th August 2025
51AQI
51AQI
31st August 2025
51AQI
51AQI
1st September 2025
43AQI
43AQI
2nd September 2025
37AQI
37AQI
3rd September 2025
35AQI
35AQI
4th September 2025
43AQI
43AQI
5th September 2025
35AQI
35AQI
6th September 2025
27AQI
27AQI
7th September 2025
30AQI
30AQI
8th September 2025
34AQI
34AQI
9th September 2025
37AQI
37AQI
10th September 2025
34AQI
34AQI
11th September 2025
29AQI
29AQI
12th September 2025
29AQI
29AQI
13th September 2025
26AQI
26AQI
14th September 2025
31AQI
31AQI
15th September 2025
32AQI
32AQI
16th September 2025
42AQI
42AQI
17th September 2025
46AQI
46AQI
18th September 2025
40AQI
40AQI
19th September 2025
31AQI
31AQI
20th September 2025
28AQI
28AQI
21st September 2025
26AQI
26AQI
22nd September 2025
25AQI
25AQI
23rd September 2025
25AQI
25AQI
24th September 2025
26AQI
26AQI
25th September 2025
46AQI
46AQI
26th September 2025
55AQI
55AQI
27th September 2025
47AQI
47AQI
28th September 2025
48AQI
48AQI
29th September 2025
59AQI
59AQI
30th September 2025
53AQI
53AQI
1st October 2025
50AQI
50AQI
2nd October 2025
48AQI
48AQI
3rd October 2025
54AQI
54AQI
4th October 2025
65AQI
65AQI
5th October 2025
56AQI
56AQI
6th October 2025
64AQI
64AQI
7th October 2025
8th October 2025
9th October 2025
10th October 2025
11th October 2025
12th October 2025
13th October 2025
14th October 2025
15th October 2025
16th October 2025
17th October 2025
18th October 2025
19th October 2025
20th October 2025
21st October 2025
22nd October 2025
23rd October 2025
24th October 2025
25th October 2025
26th October 2025
27th October 2025
28th October 2025
29th October 2025
30th October 2025
31st October 2025
1st November 2025
2nd November 2025
3rd November 2025
4th November 2025
5th November 2025
6th November 2025
7th November 2025
8th November 2025
9th November 2025
10th November 2025
11th November 2025
12th November 2025
13th November 2025
14th November 2025
15th November 2025
16th November 2025
17th November 2025
18th November 2025
19th November 2025
20th November 2025
21st November 2025
22nd November 2025
23rd November 2025
24th November 2025
25th November 2025
26th November 2025
27th November 2025
28th November 2025
29th November 2025
30th November 2025
1st December 2025
2nd December 2025
3rd December 2025
4th December 2025
5th December 2025
6th December 2025
7th December 2025
8th December 2025
9th December 2025
10th December 2025
11th December 2025
12th December 2025
13th December 2025
14th December 2025
15th December 2025
16th December 2025
17th December 2025
18th December 2025
19th December 2025
20th December 2025
21st December 2025
22nd December 2025
23rd December 2025
24th December 2025
25th December 2025
26th December 2025
27th December 2025
28th December 2025
29th December 2025
30th December 2025
31st December 2025
37AQI
34AQI
40AQI
31AQI
29AQI
35AQI
48AQI
43AQI
37AQI
56AQI
No. of days
Jan.Feb.Mar.Apr.MayJun.Jul.Aug.Sep.Oct.Nov.Dec.Total Days
202538AQI
29
2
28
26
5
29
1
30
1
29
1
24
7
25
6
27
3
2
4
249
30
Highest AQI recorded in
October56AQI
Lowest AQI recorded in
May29AQI
202440AQI
16
2
5
2
1
12
29
1
19
12
31
12
17
27
4
27
3
31
213
38
Highest AQI recorded in
September54AQI
Lowest AQI recorded in
August33AQI
202347AQI
13
6
1
16
9
2
1
18
13
2
3
3
28
3
80
34
3
1
Highest AQI recorded in
February59AQI
Lowest AQI recorded in
November21AQI
202244AQI
24
7
18
3
21
10
14
3
24
7
16
14
14
7
1
26
2
23
8
19
11
15
6
214
79
Highest AQI recorded in
August53AQI
Lowest AQI recorded in
September40AQI
202140AQI
26
5
20
8
25
5
26
4
25
6
23
7
30
1
26
5
27
3
28
3
25
5
23
8
304
60
Highest AQI recorded in
June44AQI
Lowest AQI recorded in
April37AQI
202040AQI
8
4
20
1
16
2
23
7
28
3
17
14
19
28
3
19
11
6
4
1
184
49
1
Highest AQI recorded in
December51AQI
Lowest AQI recorded in
September32AQI
Most & Least Polluted Years Over the Last 6 Years
Most Polluted Year Recorded
2023(Avg.)
47AQILeast Polluted Year Recorded
2025(Avg.)
38AQIKo's annual 2025 AQI (38) shows an average percentage change of -10.3% (improved AQI) compared to previous years: 2020 (40), 2021 (40), 2022 (44), 2023 (47), 2024 (40).
