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
22 Jul 2016 00:0027988103
23 Jul 2016 00:0018417023
24 Jul 2016 00:0017977284
25 Jul 2016 00:0022002310
26 Jul 2016 00:0021479496
27 Jul 2016 00:0021637090
28 Jul 2016 00:0020353929
29 Jul 2016 00:0018574215
30 Jul 2016 00:0018298992
31 Jul 2016 00:0020594904
1 Aug 2016 00:0020563269
2 Aug 2016 00:0020079768
3 Aug 2016 00:0021228704
4 Aug 2016 00:0021064647
5 Aug 2016 00:0019032980
6 Aug 2016 00:0016553045
7 Aug 2016 00:0017481984
8 Aug 2016 00:0020797462
9 Aug 2016 00:0020710034
10 Aug 2016 00:0018386655
11 Aug 2016 00:0017595427
12 Aug 2016 00:0016316233
13 Aug 2016 00:0014676604
14 Aug 2016 00:0015083535
15 Aug 2016 00:0017327375
16 Aug 2016 00:0017496466
17 Aug 2016 00:0018741374
18 Aug 2016 00:0018610792
19 Aug 2016 00:0017491434
20 Aug 2016 00:0014764689
21 Aug 2016 00:0015967553
22 Aug 2016 00:0018760958
23 Aug 2016 00:0018606517
24 Aug 2016 00:0020891227
25 Aug 2016 00:0020453720
26 Aug 2016 00:0017852813
27 Aug 2016 00:0015490933
28 Aug 2016 00:0016668822
29 Aug 2016 00:0019678846
30 Aug 2016 00:0019940960
31 Aug 2016 00:0022912803
1 Sep 2016 00:0020614455
2 Sep 2016 00:0018653168
3 Sep 2016 00:0015175945
4 Sep 2016 00:0016827992
5 Sep 2016 00:0020871080
6 Sep 2016 00:0021957343
7 Sep 2016 00:0025015297
8 Sep 2016 00:0022033189
9 Sep 2016 00:0018865444
10 Sep 2016 00:0016718247
11 Sep 2016 00:0018115161
12 Sep 2016 00:0022351096
13 Sep 2016 00:0022688134
14 Sep 2016 00:0025514955
15 Sep 2016 00:0022105607
16 Sep 2016 00:0019628321
17 Sep 2016 00:0016411606
18 Sep 2016 00:0019052787
19 Sep 2016 00:0023291203
20 Sep 2016 00:0024408349
21 Sep 2016 00:0029642299
22 Sep 2016 00:0030893848
23 Sep 2016 00:0025835492
24 Sep 2016 00:0022991673
25 Sep 2016 00:0024363554
26 Sep 2016 00:0030708594
27 Sep 2016 00:0030979031
28 Sep 2016 00:0030448237
29 Sep 2016 00:0033070611
30 Sep 2016 00:0030989258
1 Oct 2016 00:0026269919
2 Oct 2016 00:0026903843
3 Oct 2016 00:0031532742
4 Oct 2016 00:0031623831
5 Oct 2016 00:0031298294
6 Oct 2016 00:0032858436
7 Oct 2016 00:0030605979
8 Oct 2016 00:0028074666
9 Oct 2016 00:0026253609
10 Oct 2016 00:0031610214
11 Oct 2016 00:0031615384
12 Oct 2016 00:0032762516
13 Oct 2016 00:0035127124
14 Oct 2016 00:0031830945
15 Oct 2016 00:0025558341
16 Oct 2016 00:0026663325
17 Oct 2016 00:0031557804
18 Oct 2016 00:0032947258
19 Oct 2016 00:0033244866
20 Oct 2016 00:0035348101
21 Oct 2016 00:0028940846
22 Oct 2016 00:0026717800
23 Oct 2016 00:0026768761
24 Oct 2016 00:0032893166
25 Oct 2016 00:0031922615
26 Oct 2016 00:0030140887
27 Oct 2016 00:0027209311
28 Oct 2016 00:0022178026
29 Oct 2016 00:0019129258
30 Oct 2016 00:0021318060
31 Oct 2016 00:0023299931
1 Nov 2016 00:0024402896
2 Nov 2016 00:0026355258
3 Nov 2016 00:0025909551
4 Nov 2016 00:0023480946
5 Nov 2016 00:0020199931
6 Nov 2016 00:0022447545
7 Nov 2016 00:0028036560
8 Nov 2016 00:0030319676
9 Nov 2016 00:0035729277
10 Nov 2016 00:0028236920
11 Nov 2016 00:0023899624
12 Nov 2016 00:0020133392
13 Nov 2016 00:0022264924
14 Nov 2016 00:0027186467
15 Nov 2016 00:0030446593
16 Nov 2016 00:0030784832
17 Nov 2016 00:0029370094
18 Nov 2016 00:0026674972
19 Nov 2016 00:0022262511
20 Nov 2016 00:0025073502
21 Nov 2016 00:0031263002
22 Nov 2016 00:0030925019
23 Nov 2016 00:0029816114
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

Response time

Mean global response time, ms, from Pingdom:

DateResponse time (ms)
11 Jan 2017 20:00115
11 Jan 2017 21:00106
11 Jan 2017 22:00112
11 Jan 2017 23:00107
12 Jan 2017 00:00100
12 Jan 2017 01:00101
12 Jan 2017 02:00100
12 Jan 2017 03:00106
12 Jan 2017 04:0094
12 Jan 2017 05:0097
12 Jan 2017 06:00109
12 Jan 2017 07:0099
12 Jan 2017 08:00116
12 Jan 2017 09:0097
12 Jan 2017 10:00115
12 Jan 2017 11:00118
12 Jan 2017 12:00107
12 Jan 2017 13:00126
12 Jan 2017 14:00117
12 Jan 2017 15:00149
12 Jan 2017 16:00114
12 Jan 2017 17:0092
12 Jan 2017 18:0091
12 Jan 2017 19:0076
12 Jan 2017 20:0081
12 Jan 2017 21:0075
12 Jan 2017 22:0082
12 Jan 2017 23:0081
13 Jan 2017 00:0074
13 Jan 2017 01:0081
13 Jan 2017 02:0086
13 Jan 2017 03:0082
13 Jan 2017 04:0078
13 Jan 2017 05:0077
13 Jan 2017 06:0080
13 Jan 2017 07:0084
13 Jan 2017 08:0086
13 Jan 2017 09:0079
13 Jan 2017 10:0084
13 Jan 2017 11:00101
13 Jan 2017 12:0077
13 Jan 2017 13:0088
13 Jan 2017 14:0091
13 Jan 2017 15:00101
13 Jan 2017 16:00107
13 Jan 2017 17:0086
13 Jan 2017 18:0083
13 Jan 2017 19:0091
13 Jan 2017 20:0088
13 Jan 2017 21:0093
13 Jan 2017 22:00100
13 Jan 2017 23:0082
14 Jan 2017 00:0089
14 Jan 2017 01:0085
14 Jan 2017 02:0093
14 Jan 2017 03:0086
14 Jan 2017 04:0080
14 Jan 2017 05:0089
14 Jan 2017 06:0083
14 Jan 2017 07:0098
14 Jan 2017 08:0091
14 Jan 2017 09:0090
14 Jan 2017 10:0099
14 Jan 2017 11:0092
14 Jan 2017 12:0089
14 Jan 2017 13:0093
14 Jan 2017 14:00110
14 Jan 2017 15:00113
14 Jan 2017 16:0089
14 Jan 2017 17:00100
14 Jan 2017 18:00122
14 Jan 2017 19:0093
14 Jan 2017 20:0096
14 Jan 2017 21:0097
14 Jan 2017 22:0090
14 Jan 2017 23:0094
15 Jan 2017 00:00101
15 Jan 2017 01:0088
15 Jan 2017 02:0088
15 Jan 2017 03:00102
15 Jan 2017 04:0092
15 Jan 2017 05:0094
15 Jan 2017 06:0098
15 Jan 2017 07:00104
15 Jan 2017 08:00105
15 Jan 2017 09:0085
15 Jan 2017 10:00118
15 Jan 2017 11:0092
15 Jan 2017 12:00119
15 Jan 2017 13:00101
15 Jan 2017 14:0099
15 Jan 2017 15:00139
15 Jan 2017 16:00124
15 Jan 2017 17:00121
15 Jan 2017 18:00104
15 Jan 2017 19:00102
15 Jan 2017 20:00104
15 Jan 2017 21:0095
15 Jan 2017 22:00103
15 Jan 2017 23:00103
16 Jan 2017 00:0094
16 Jan 2017 01:00107
16 Jan 2017 02:00120
16 Jan 2017 03:0095
16 Jan 2017 04:00106
16 Jan 2017 05:00101
16 Jan 2017 06:0088
16 Jan 2017 07:00104
16 Jan 2017 08:0098
16 Jan 2017 09:0095
16 Jan 2017 10:0095
16 Jan 2017 11:0091
16 Jan 2017 12:0089
16 Jan 2017 13:0098
16 Jan 2017 14:0094
16 Jan 2017 15:00102
16 Jan 2017 16:0093
16 Jan 2017 17:0089
16 Jan 2017 18:0097
16 Jan 2017 19:00103
16 Jan 2017 20:0099
16 Jan 2017 21:0099
16 Jan 2017 22:0089
16 Jan 2017 23:0095
17 Jan 2017 00:0089
17 Jan 2017 01:0088
17 Jan 2017 02:0093
17 Jan 2017 03:0088
17 Jan 2017 04:0088
17 Jan 2017 05:0095
17 Jan 2017 06:0096
17 Jan 2017 07:0083
17 Jan 2017 08:0088
17 Jan 2017 09:0098
17 Jan 2017 10:00106
17 Jan 2017 11:0092
17 Jan 2017 12:0094
17 Jan 2017 13:0092
17 Jan 2017 14:0091
17 Jan 2017 15:0093
17 Jan 2017 16:00111
17 Jan 2017 17:0096
17 Jan 2017 18:00106
17 Jan 2017 19:0091
17 Jan 2017 20:0087
17 Jan 2017 21:00101
17 Jan 2017 22:0095
17 Jan 2017 23:0088
18 Jan 2017 00:0093
18 Jan 2017 01:0091
18 Jan 2017 02:0085
18 Jan 2017 03:0094
18 Jan 2017 04:0097
18 Jan 2017 05:00140
18 Jan 2017 06:00109
18 Jan 2017 07:00115
18 Jan 2017 08:00118
18 Jan 2017 09:00104
18 Jan 2017 10:00141
18 Jan 2017 11:0099
18 Jan 2017 12:00212
18 Jan 2017 13:00158
18 Jan 2017 14:0090
18 Jan 2017 15:0087
18 Jan 2017 16:00112
18 Jan 2017 17:0098
18 Jan 2017 18:00104
18 Jan 2017 19:00104
18 Jan 2017 20:00101

Caching

Hit ratio, last 7 days, from Fastly:

Cache resultRequests
Hits4183430791
Misses123096965

Availability

Total downtime, according to Pingdom:

Last 30 daysNone
Last 3 monthsan hour
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
IAD 14436
617ms
(71ms)
DFW 12197
690ms
(86ms)

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.