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
24 Nov 2016 00:0027293499
25 Nov 2016 00:0026902168
26 Nov 2016 00:0022597621
27 Nov 2016 00:0024901236
28 Nov 2016 00:0032238266
29 Nov 2016 00:0031756367
30 Nov 2016 00:0031972402
1 Dec 2016 00:0030561717
2 Dec 2016 00:0025721499
3 Dec 2016 00:0022570148
4 Dec 2016 00:0023583934
5 Dec 2016 00:0029746317
6 Dec 2016 00:0028589146
7 Dec 2016 00:0028071204
8 Dec 2016 00:0027172091
9 Dec 2016 00:0025654051
10 Dec 2016 00:0023840512
11 Dec 2016 00:0027162970
12 Dec 2016 00:0029199457
13 Dec 2016 00:0030700233
14 Dec 2016 00:0028966255
15 Dec 2016 00:0027179634
16 Dec 2016 00:0023121747
17 Dec 2016 00:0019178732
18 Dec 2016 00:0020423247
19 Dec 2016 00:0025638517
20 Dec 2016 00:0030054247
21 Dec 2016 00:0027293125
22 Dec 2016 00:0028253934
23 Dec 2016 00:0025218199
24 Dec 2016 00:0020462590
25 Dec 2016 00:0019624526
26 Dec 2016 00:0025538280
27 Dec 2016 00:0028313547
28 Dec 2016 00:0027086156
29 Dec 2016 00:0026405218
30 Dec 2016 00:0024943598
31 Dec 2016 00:0021225557
1 Jan 2017 00:0020654814
2 Jan 2017 00:0025885081
3 Jan 2017 00:0029892864
4 Jan 2017 00:0030166919
5 Jan 2017 00:0030594723
6 Jan 2017 00:0029425708
7 Jan 2017 00:0025402726
8 Jan 2017 00:0025982172
9 Jan 2017 00:0032314246
10 Jan 2017 00:0031809252
11 Jan 2017 00:0032536835
12 Jan 2017 00:0032799886
13 Jan 2017 00:0029391192
14 Jan 2017 00:0025300299
15 Jan 2017 00:0027282852
16 Jan 2017 00:0032524907
17 Jan 2017 00:0032415786
18 Jan 2017 00:0033365658
19 Jan 2017 00:0035120602
20 Jan 2017 00:0041188974
21 Jan 2017 00:0030927077
22 Jan 2017 00:0029338687
23 Jan 2017 00:0034284932
24 Jan 2017 00:0034671031
25 Jan 2017 00:0035619948
26 Jan 2017 00:0036071213
27 Jan 2017 00:0032465983
28 Jan 2017 00:0026966448
29 Jan 2017 00:0029740069
30 Jan 2017 00:0036063509
31 Jan 2017 00:0036152486
1 Feb 2017 00:0038016618
2 Feb 2017 00:0038092744
3 Feb 2017 00:0036796339
4 Feb 2017 00:0032491273
5 Feb 2017 00:0032453018
6 Feb 2017 00:0036860319
7 Feb 2017 00:0035571731
8 Feb 2017 00:0036412197
9 Feb 2017 00:0036514897
10 Feb 2017 00:0033490604
11 Feb 2017 00:0027995607
12 Feb 2017 00:0029223036
13 Feb 2017 00:0036885381
14 Feb 2017 00:0035887992
15 Feb 2017 00:0038363219
16 Feb 2017 00:0038642420
17 Feb 2017 00:0034407156
18 Feb 2017 00:0028874822
19 Feb 2017 00:0030971428
20 Feb 2017 00:0037275115
21 Feb 2017 00:0038420294
22 Feb 2017 00:0037623473
23 Feb 2017 00:0039089757
24 Feb 2017 00:0036219130
25 Feb 2017 00:0034519605
26 Feb 2017 00:0035891521
27 Feb 2017 00:0043712007
28 Feb 2017 00:0045064797
1 Mar 2017 00:0045392374
2 Mar 2017 00:0046631873
3 Mar 2017 00:0042165614
4 Mar 2017 00:0037713394
5 Mar 2017 00:0039805594
6 Mar 2017 00:0046066982
7 Mar 2017 00:0045176879
8 Mar 2017 00:0044774385
9 Mar 2017 00:0047826146
10 Mar 2017 00:0045210137
11 Mar 2017 00:0037960796
12 Mar 2017 00:0038080093
13 Mar 2017 00:0044997769
14 Mar 2017 00:0044341787
15 Mar 2017 00:0045435363
16 Mar 2017 00:0046967559
17 Mar 2017 00:0043404160
18 Mar 2017 00:0038636175
19 Mar 2017 00:0040990946
20 Mar 2017 00:0046873678
21 Mar 2017 00:0046191872
22 Mar 2017 00:0054879586
23 Mar 2017 00:0051247835
24 Mar 2017 00:0043630492
25 Mar 2017 00:0037657863
26 Mar 2017 00:0038374304
27 Mar 2017 00:0046018476
28 Mar 2017 00:0047087794
29 Mar 2017 00:0050447958
30 Mar 2017 00:0051112994
31 Mar 2017 00:0047293919
1 Apr 2017 00:0041000670
2 Apr 2017 00:0043531550
3 Apr 2017 00:0051512891
4 Apr 2017 00:0051372073
5 Apr 2017 00:0054481975
6 Apr 2017 00:0056145273
7 Apr 2017 00:0052098787
8 Apr 2017 00:0043880878
9 Apr 2017 00:0045799887
10 Apr 2017 00:0053918800
11 Apr 2017 00:0052654208
12 Apr 2017 00:0052502250
13 Apr 2017 00:0054089240
14 Apr 2017 00:0046311543
15 Apr 2017 00:0041134631
16 Apr 2017 00:0041256184
17 Apr 2017 00:0049758481
18 Apr 2017 00:0052956422
19 Apr 2017 00:0062803694
20 Apr 2017 00:0057519252
21 Apr 2017 00:0052213352
22 Apr 2017 00:0044706951
23 Apr 2017 00:0046211183
24 Apr 2017 00:0051760510
25 Apr 2017 00:0052904021
26 Apr 2017 00:0054639242
27 Apr 2017 00:0054814559
28 Apr 2017 00:0049165192
29 Apr 2017 00:0041450175
30 Apr 2017 00:0042086729
1 May 2017 00:0048927702
2 May 2017 00:0052240395
3 May 2017 00:0054854825
4 May 2017 00:0056176590
5 May 2017 00:0049582172
6 May 2017 00:0042364406
7 May 2017 00:0045425783
8 May 2017 00:0055427229
9 May 2017 00:0053459291
10 May 2017 00:0058407788
11 May 2017 00:0055479307
12 May 2017 00:0052323298
13 May 2017 00:0046430394
14 May 2017 00:0046762851
15 May 2017 00:0072273424
16 May 2017 00:00122376199
17 May 2017 00:00146982847
18 May 2017 00:00149453129
19 May 2017 00:00132430263
20 May 2017 00:00103930642
21 May 2017 00:00113328523
22 May 2017 00:00156497089

Response time

Mean global response time, ms, from Pingdom:

DateResponse time (ms)
16 May 2017 01:00304
16 May 2017 02:00300
16 May 2017 03:00304
16 May 2017 04:00314
16 May 2017 05:00298
16 May 2017 06:00306
16 May 2017 07:00312
16 May 2017 08:00311
16 May 2017 09:00303
16 May 2017 10:00322
16 May 2017 11:00504
16 May 2017 12:00375
16 May 2017 13:00342
16 May 2017 14:00340
16 May 2017 15:00315
16 May 2017 16:00320
16 May 2017 17:00316
16 May 2017 18:00327
16 May 2017 19:00334
16 May 2017 20:00330
16 May 2017 21:00322
16 May 2017 22:00331
16 May 2017 23:00316
17 May 2017 00:00315
17 May 2017 01:00322
17 May 2017 02:00317
17 May 2017 03:00313
17 May 2017 04:00323
17 May 2017 05:00315
17 May 2017 06:00325
17 May 2017 07:00361
17 May 2017 08:00411
17 May 2017 09:00342
17 May 2017 10:00333
17 May 2017 11:00347
17 May 2017 12:00325
17 May 2017 13:00313
17 May 2017 14:00335
17 May 2017 15:00310
17 May 2017 16:00327
17 May 2017 17:00336
17 May 2017 18:00314
17 May 2017 19:00308
17 May 2017 20:00324
17 May 2017 21:00323
17 May 2017 22:00318
17 May 2017 23:00325
18 May 2017 00:00326
18 May 2017 01:00314
18 May 2017 02:00319
18 May 2017 03:00310
18 May 2017 04:00312
18 May 2017 05:00343
18 May 2017 06:00324
18 May 2017 07:00315
18 May 2017 08:00328
18 May 2017 09:00317
18 May 2017 10:00318
18 May 2017 11:00320
18 May 2017 12:00327
18 May 2017 13:00317
18 May 2017 14:00319
18 May 2017 15:00371
18 May 2017 16:00436
18 May 2017 17:00326
18 May 2017 18:00359
18 May 2017 19:00318
18 May 2017 20:00327
18 May 2017 21:00336
18 May 2017 22:00326
18 May 2017 23:00317
19 May 2017 00:00311
19 May 2017 01:00322
19 May 2017 02:00328
19 May 2017 03:00315
19 May 2017 04:00329
19 May 2017 05:00352
19 May 2017 06:00325
19 May 2017 07:00327
19 May 2017 08:00333
19 May 2017 09:00341
19 May 2017 10:00327
19 May 2017 11:00330
19 May 2017 12:00342
19 May 2017 13:00340
19 May 2017 14:00347
19 May 2017 15:00331
19 May 2017 16:00323
19 May 2017 17:00327
19 May 2017 18:00330
19 May 2017 19:00319
19 May 2017 20:00332
19 May 2017 21:00326
19 May 2017 22:00322
19 May 2017 23:00328
20 May 2017 00:00330
20 May 2017 01:00325
20 May 2017 02:00329
20 May 2017 03:00324
20 May 2017 04:00327
20 May 2017 05:00338
20 May 2017 06:00320
20 May 2017 07:00337
20 May 2017 08:00329
20 May 2017 09:00320
20 May 2017 10:00320
20 May 2017 11:00314
20 May 2017 12:00327
20 May 2017 13:00335
20 May 2017 14:00343
20 May 2017 15:00334
20 May 2017 16:00326
20 May 2017 17:00350
20 May 2017 18:00340
20 May 2017 19:00331
20 May 2017 20:00348
20 May 2017 21:00317
20 May 2017 22:00295
20 May 2017 23:00287
21 May 2017 00:00278
21 May 2017 01:00276
21 May 2017 02:00281
21 May 2017 03:00279
21 May 2017 04:00278
21 May 2017 05:00283
21 May 2017 06:00275
21 May 2017 07:00275
21 May 2017 08:00280
21 May 2017 09:00273
21 May 2017 10:00270
21 May 2017 11:00268
21 May 2017 12:00277
21 May 2017 13:00274
21 May 2017 14:00280
21 May 2017 15:00264
21 May 2017 16:00277
21 May 2017 17:00284
21 May 2017 18:00304
21 May 2017 19:00278
21 May 2017 20:00283
21 May 2017 21:00287
21 May 2017 22:00277
21 May 2017 23:00274
22 May 2017 00:00276
22 May 2017 01:00295
22 May 2017 02:00281
22 May 2017 03:00288
22 May 2017 04:00273
22 May 2017 05:00281
22 May 2017 06:00289
22 May 2017 07:00285
22 May 2017 08:00275
22 May 2017 09:00268
22 May 2017 10:00275
22 May 2017 11:00280
22 May 2017 12:00273
22 May 2017 13:00272
22 May 2017 14:00274
22 May 2017 15:00284
22 May 2017 16:00282
22 May 2017 17:00303
22 May 2017 18:00315
22 May 2017 19:00287
22 May 2017 20:00276
22 May 2017 21:00267
22 May 2017 22:00271
22 May 2017 23:00269
23 May 2017 00:00281
23 May 2017 01:00287

Caching

Hit ratio, last 7 days, from Fastly:

Cache resultRequests
Hits6957672958
Misses331284356

Availability

Total downtime, according to Pingdom:

Last 30 daysNone
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
LHR 65,788
525ms
(67ms)
HHN 17,679
924ms
(98ms)
IAD 12,246
725ms
(85ms)
DFW 10,112
841ms
(77ms)

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.