jsDelivr vs serpstack

Same instrument, two spec sheets — measured, not claimed.

Uptime · 30d
Uptime · 90d100%99.02%
Uptime · 30d100%98.3%
P50 · ms181492
P95 · ms10571442
AuthnoneapiKey
CORSyesno
HTTPSyesyes
Card requirednono
Commercial useunclearunclear
Data licenseUnverifiedUnverified
Free tierFree, no keyFree tier — key may be required
Rate limitUnpublishedUnpublished
In directory since2026-07-052026-07-05
operationalpartialdownno data

jsDelivr vs serpstack: common questions

Which is more reliable, jsDelivr or serpstack?

On our scheduled checks, jsDelivr leads on measured uptime — jsDelivr at 100% versus serpstack at 99.02% over 90 days. These are our own probe results, not provider claims; the uptime bars above show the day-by-day record for both.

Which is faster, jsDelivr or serpstack?

jsDelivr has the lower median latency in our checks — jsDelivr responds in 181 ms versus serpstack at 492 ms (P50). Tail latency (P95) is in the table above; for most workloads the median is the number that shapes how the API feels.

Do jsDelivr and serpstack need an API key?

jsDelivr needs no key, while serpstack requires a free API key. If you want to start calling without signup, reach for jsDelivr first.

Can I call jsDelivr and serpstack from the browser?

Only jsDelivr is browser-friendly — it returns CORS headers over HTTPS. serpstack needs a server-side call or proxy, so factor that into which one fits a front-end project.

Are jsDelivr and serpstack free for commercial use?

jsDelivr has unclear commercial terms, and serpstack has unclear commercial terms. We track service terms and the data license as separate fields — see the Commercial use and Data license rows above, and confirm both before shipping either in a paid product.