Advice Slip vs Zen Quotes

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

Uptime · 30d
Uptime · 90d62.7%90.2%
Uptime · 30d61.7%86.7%
P50 · ms7471657
P95 · ms49604714
Authnonenone
CORSyesno
HTTPSyesyes
Card requirednono
Commercial useunclearunclear
Data licenseUnverifiedUnverified
Free tierFree — limits not publishedFree — no key
Rate limitUnpublishedRate-limited on the free tier (see zenquotes.io)
In directory since2026-07-052026-07-05
operationalpartialdownno data

Advice Slip vs Zen Quotes: common questions

Which is more reliable, Advice Slip or Zen Quotes?

On our scheduled checks, Zen Quotes leads on measured uptime — Advice Slip at 62.7% versus Zen Quotes at 90.2% 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, Advice Slip or Zen Quotes?

Advice Slip has the lower median latency in our checks — Advice Slip responds in 747 ms versus Zen Quotes at 1657 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 Advice Slip and Zen Quotes need an API key?

Neither needs a paid key — Advice Slip is callable with no signup, and Zen Quotes is callable with no signup. Both are quick to prototype with; rate limits still apply.

Can I call Advice Slip and Zen Quotes from the browser?

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

Are Advice Slip and Zen Quotes free for commercial use?

Advice Slip has unclear commercial terms, and Zen Quotes 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.