Polyfill.io

Usage and performance

The public instance of the polyfill service is hosted by the Financial Times, with the generous support of Fastly, who provide CDN distribution. View Fastly network map

Traffic volume

This shows the number of requests we have served per day, over the last 180 days, measured by Fastly:

DateRequests
30 Sep 2016 00:0086
1 Oct 2016 00:0043
2 Oct 2016 00:0071
3 Oct 2016 00:00226
4 Oct 2016 00:00160
5 Oct 2016 00:00110
6 Oct 2016 00:001579
7 Oct 2016 00:0048
8 Oct 2016 00:0064
9 Oct 2016 00:0067
10 Oct 2016 00:00149
11 Oct 2016 00:00223
12 Oct 2016 00:0078
13 Oct 2016 00:0081
14 Oct 2016 00:00118
15 Oct 2016 00:0055
16 Oct 2016 00:0070
17 Oct 2016 00:0063
18 Oct 2016 00:00103
19 Oct 2016 00:00157
20 Oct 2016 00:00236
21 Oct 2016 00:0047
22 Oct 2016 00:0079
23 Oct 2016 00:00204
24 Oct 2016 00:0091
25 Oct 2016 00:0064
26 Oct 2016 00:0065
27 Oct 2016 00:0076
28 Oct 2016 00:0097
29 Oct 2016 00:0077
30 Oct 2016 00:0049
31 Oct 2016 00:0034
1 Nov 2016 00:0096
2 Nov 2016 00:0065
3 Nov 2016 00:0080
4 Nov 2016 00:00100
5 Nov 2016 00:0030
6 Nov 2016 00:0040
7 Nov 2016 00:0078
8 Nov 2016 00:0072
9 Nov 2016 00:0034
10 Nov 2016 00:0054889
11 Nov 2016 00:00679929
12 Nov 2016 00:00825820
13 Nov 2016 00:00814720
14 Nov 2016 00:001021753
15 Nov 2016 00:001102019
16 Nov 2016 00:001099720
17 Nov 2016 00:001123739
18 Nov 2016 00:0067517
19 Nov 2016 00:0035108
20 Nov 2016 00:0031363
21 Nov 2016 00:0028867
22 Nov 2016 00:0040263
23 Nov 2016 00:0032979
24 Nov 2016 00:0024253
25 Nov 2016 00:0022254
26 Nov 2016 00:0022030
27 Nov 2016 00:0018731
28 Nov 2016 00:00182565
29 Nov 2016 00:001140876
30 Nov 2016 00:001186124
1 Dec 2016 00:001122908
2 Dec 2016 00:001395852
3 Dec 2016 00:002909070
4 Dec 2016 00:002038248
5 Dec 2016 00:002301520
6 Dec 2016 00:001214877
7 Dec 2016 00:001095901
8 Dec 2016 00:001064559
9 Dec 2016 00:001046807
10 Dec 2016 00:00904317
11 Dec 2016 00:00940400
12 Dec 2016 00:001213397
13 Dec 2016 00:001743987
14 Dec 2016 00:001664367
15 Dec 2016 00:001175534
16 Dec 2016 00:00999240
17 Dec 2016 00:00832129
18 Dec 2016 00:00835799
19 Dec 2016 00:001053727
20 Dec 2016 00:001189654
21 Dec 2016 00:001077093
22 Dec 2016 00:001022188
23 Dec 2016 00:00872246
24 Dec 2016 00:00726560
25 Dec 2016 00:00620632
26 Dec 2016 00:00834653
27 Dec 2016 00:00989326
28 Dec 2016 00:001089302
29 Dec 2016 00:001028335
30 Dec 2016 00:00979850
31 Dec 2016 00:00818599
1 Jan 2017 00:00785550
2 Jan 2017 00:001001862
3 Jan 2017 00:001194243
4 Jan 2017 00:001162339
5 Jan 2017 00:001159689
6 Jan 2017 00:001239661
7 Jan 2017 00:00911146
8 Jan 2017 00:00922117
9 Jan 2017 00:001143238
10 Jan 2017 00:001171298
11 Jan 2017 00:001116548
12 Jan 2017 00:001075348
13 Jan 2017 00:001011575
14 Jan 2017 00:00864698
15 Jan 2017 00:00880394
16 Jan 2017 00:001129440
17 Jan 2017 00:001157111
18 Jan 2017 00:001139520
19 Jan 2017 00:001121942
20 Jan 2017 00:001052632
21 Jan 2017 00:00913862
22 Jan 2017 00:00928253
23 Jan 2017 00:001169071
24 Jan 2017 00:001196641
25 Jan 2017 00:001214401
26 Jan 2017 00:001176595
27 Jan 2017 00:001306732
28 Jan 2017 00:00924800
29 Jan 2017 00:00902466
30 Jan 2017 00:001189629
31 Jan 2017 00:001288818
1 Feb 2017 00:001260071
2 Feb 2017 00:001218221
3 Feb 2017 00:001136667
4 Feb 2017 00:00937479
5 Feb 2017 00:00921339
6 Feb 2017 00:001486885
7 Feb 2017 00:001740900
8 Feb 2017 00:001576894
9 Feb 2017 00:001682646
10 Feb 2017 00:001875474
11 Feb 2017 00:001466423
12 Feb 2017 00:001525392
13 Feb 2017 00:001722796
14 Feb 2017 00:001306673
15 Feb 2017 00:001609494
16 Feb 2017 00:002066694
17 Feb 2017 00:001829938
18 Feb 2017 00:001679947
19 Feb 2017 00:001515341
20 Feb 2017 00:001808193
21 Feb 2017 00:001813746
22 Feb 2017 00:001803143
23 Feb 2017 00:001972123
24 Feb 2017 00:001740502
25 Feb 2017 00:001482780
26 Feb 2017 00:001457243
27 Feb 2017 00:002533323
28 Feb 2017 00:002404856
1 Mar 2017 00:001785961
2 Mar 2017 00:001752016
3 Mar 2017 00:001739087
4 Mar 2017 00:001432189
5 Mar 2017 00:001368342
6 Mar 2017 00:001628094
7 Mar 2017 00:001576257
8 Mar 2017 00:001745063
9 Mar 2017 00:001912650
10 Mar 2017 00:001921660
11 Mar 2017 00:001583584
12 Mar 2017 00:002066790
13 Mar 2017 00:002026988
14 Mar 2017 00:001282127
15 Mar 2017 00:00111034
16 Mar 2017 00:00233995
17 Mar 2017 00:00442769
18 Mar 2017 00:00339077
19 Mar 2017 00:00330613
20 Mar 2017 00:00406811
21 Mar 2017 00:00346066
22 Mar 2017 00:00387065
23 Mar 2017 00:00337621
24 Mar 2017 00:00294561
25 Mar 2017 00:00216200
26 Mar 2017 00:00206510
27 Mar 2017 00:00302041
28 Mar 2017 00:00301625

Response time

Mean global response time, ms, from Pingdom:

DateResponse time (ms)
22 Mar 2017 21:00468
22 Mar 2017 22:00415
22 Mar 2017 23:00407
23 Mar 2017 00:00374
23 Mar 2017 01:00397
23 Mar 2017 02:00381
23 Mar 2017 03:00383
23 Mar 2017 04:00398
23 Mar 2017 05:00387
23 Mar 2017 06:00374
23 Mar 2017 07:00375
23 Mar 2017 08:00368
23 Mar 2017 09:00383
23 Mar 2017 10:00368
23 Mar 2017 11:00383
23 Mar 2017 12:00384
23 Mar 2017 13:00378
23 Mar 2017 14:00385
23 Mar 2017 15:00379
23 Mar 2017 16:00372
23 Mar 2017 17:00371
23 Mar 2017 18:00375
23 Mar 2017 19:00377
23 Mar 2017 20:00351
23 Mar 2017 21:00370
23 Mar 2017 22:00349
23 Mar 2017 23:00361
24 Mar 2017 00:00358
24 Mar 2017 01:00341
24 Mar 2017 02:00356
24 Mar 2017 03:00355
24 Mar 2017 04:00370
24 Mar 2017 05:00365
24 Mar 2017 06:00348
24 Mar 2017 07:00356
24 Mar 2017 08:00357
24 Mar 2017 09:00359
24 Mar 2017 10:00352
24 Mar 2017 11:00392
24 Mar 2017 12:00396
24 Mar 2017 13:00402
24 Mar 2017 14:00412
24 Mar 2017 15:00393
24 Mar 2017 16:00377
24 Mar 2017 17:00403
24 Mar 2017 18:00394
24 Mar 2017 19:00406
24 Mar 2017 20:00404
24 Mar 2017 21:00432
24 Mar 2017 22:00401
24 Mar 2017 23:00404
25 Mar 2017 00:00412
25 Mar 2017 01:00406
25 Mar 2017 02:00391
25 Mar 2017 03:00393
25 Mar 2017 04:00401
25 Mar 2017 05:00413
25 Mar 2017 06:00411
25 Mar 2017 07:00403
25 Mar 2017 08:00413
25 Mar 2017 09:00384
25 Mar 2017 10:00371
25 Mar 2017 11:00401
25 Mar 2017 12:00395
25 Mar 2017 13:00395
25 Mar 2017 14:00391
25 Mar 2017 15:00395
25 Mar 2017 16:00378
25 Mar 2017 17:00380
25 Mar 2017 18:00376
25 Mar 2017 19:00381
25 Mar 2017 20:00385
25 Mar 2017 21:00403
25 Mar 2017 22:00378
25 Mar 2017 23:00364
26 Mar 2017 00:00380
26 Mar 2017 01:00381
26 Mar 2017 02:00385
26 Mar 2017 03:00385
26 Mar 2017 04:00376
26 Mar 2017 05:00379
26 Mar 2017 06:00384
26 Mar 2017 07:00384
26 Mar 2017 08:00375
26 Mar 2017 09:00375
26 Mar 2017 10:00374
26 Mar 2017 11:00394
26 Mar 2017 12:00378
26 Mar 2017 13:00383
26 Mar 2017 14:00391
26 Mar 2017 15:00387
26 Mar 2017 16:00393
26 Mar 2017 17:00379
26 Mar 2017 18:00376
26 Mar 2017 19:00384
26 Mar 2017 20:00371
26 Mar 2017 21:00378
26 Mar 2017 22:00361
26 Mar 2017 23:00350
27 Mar 2017 00:00351
27 Mar 2017 01:00352
27 Mar 2017 02:00346
27 Mar 2017 03:00364
27 Mar 2017 04:00342
27 Mar 2017 05:00347
27 Mar 2017 06:00371
27 Mar 2017 07:00352
27 Mar 2017 08:00347
27 Mar 2017 09:00354
27 Mar 2017 10:00346
27 Mar 2017 11:00356
27 Mar 2017 12:00312
27 Mar 2017 13:00329
27 Mar 2017 14:00318
27 Mar 2017 15:00317
27 Mar 2017 16:00344
27 Mar 2017 17:00337
27 Mar 2017 18:00320
27 Mar 2017 19:00310
27 Mar 2017 20:00325
27 Mar 2017 21:00319
27 Mar 2017 22:00316
27 Mar 2017 23:00312
28 Mar 2017 00:00319
28 Mar 2017 01:00325
28 Mar 2017 02:00311
28 Mar 2017 03:00308
28 Mar 2017 04:00321
28 Mar 2017 05:00310
28 Mar 2017 06:00321
28 Mar 2017 07:00310
28 Mar 2017 08:00318
28 Mar 2017 09:00310
28 Mar 2017 10:00314
28 Mar 2017 11:00314
28 Mar 2017 12:00320
28 Mar 2017 13:00334
28 Mar 2017 14:00324
28 Mar 2017 15:00309
28 Mar 2017 16:00328
28 Mar 2017 17:00342
28 Mar 2017 18:00336
28 Mar 2017 19:00336
28 Mar 2017 20:00319
28 Mar 2017 21:00325
28 Mar 2017 22:00341
28 Mar 2017 23:00332
29 Mar 2017 00:00347
29 Mar 2017 01:00349
29 Mar 2017 02:00318
29 Mar 2017 03:00322
29 Mar 2017 04:00316
29 Mar 2017 05:00304
29 Mar 2017 06:00308
29 Mar 2017 07:00323
29 Mar 2017 08:00306
29 Mar 2017 09:00308
29 Mar 2017 10:00322
29 Mar 2017 11:00309
29 Mar 2017 12:00313
29 Mar 2017 13:00308
29 Mar 2017 14:00324
29 Mar 2017 15:00315
29 Mar 2017 16:00324
29 Mar 2017 17:00312
29 Mar 2017 18:00306
29 Mar 2017 19:00321
29 Mar 2017 20:00320
29 Mar 2017 21:00359

Caching

Hit ratio, last 7 days, from Fastly:

Cache resultRequests
Hits148834891
Misses2732498

Availability

Total downtime, according to Pingdom:

Last 30 days18 minutes
Last 3 months18 minutes
Last 12 monthsan hour

Caching responses that vary by User-Agent is very hard to do with good cache performance. We use a custom Fastly VCL configuration that separates the UA normalisation from the polyfill bundle.

Network performance in detail

95th percentile and median resource timing metrics, broken down by Fastly edge point of presence, measured using the resource timing API from live polyfill service requests that opted in to anonymously report performance data. Last 30 days, showing only POPs that have served more than 10000 RUM-enabled requests.

PoP Sample Per connection phase (95th percentile and median) Overall
LCY 45,862
1,184ms
(129ms)
HHN 32,337
1,333ms
(184ms)
IAD 20,492
1,083ms
(71ms)
DFW 17,539
1,097ms
(91ms)
AMS 16,793
1,775ms
(184ms)
ORD 10,339
1,060ms
(95ms)

Only non-zero samples are counted, which in practice means there are far fewer DNS lookup and TCP connect datapoints, because if reusing a keep-alive connection, both will be zero. Timings for individual connection phases do not sum to the overall RTT because, for example, the request that exhibits the 95th percentile DNS time, will most likely not also be the 95th percentile on all other connection metrics.

Typically Polyfill.io is loaded at a point where the browser is very busy. To speed up loading, consider using preconnect or preload.