Cloudflare Analytics Sampling Explained Cloudflare Analytics Sampling Explained | Zhiwei Li

Cloudflare Analytics Sampling Explained | Generated by AI

Home 2026.04

Question: What does “sample by 10% requests” in Cloudflare mean? And why do all path counts end with 0?

Answer:

When Cloudflare shows “sampled by 10% requests”, it means:

  • Cloudflare does NOT count every request
  • It only records about 10% of traffic
  • Then it scales the numbers up to estimate totals

Example:

  • Real requests = 53,270
  • Cloudflare samples 10% → collects ≈ 5,327
  • Then multiplies by 10 → reports ≈ 53,270 (estimated)

Cloudflare explicitly states that when sampling is 10%, it samples a subset and multiplies to estimate the full dataset. (Cloudflare Docs)


Why all numbers end with 0

Yes — this is exactly because of 10% sampling.

If Cloudflare:

  • samples 1 out of 10 requests
  • then multiplies results by 10

All returned values will usually be:

  • multiples of 10
  • sometimes rounded
  • sometimes slightly off

So you get:

430
290
210
170
150
130
120

instead of:

427
291
213
168
152
131
119

Because the real counts are estimated, not exact.


Important: your data is approximate

This affects:

  • Referers
  • Paths
  • Countries
  • User agents
  • Bots
  • etc.

But NOT usually:

  • total requests
  • bandwidth
  • top-level metrics

Cloudflare does this because your site may have millions of events, and sampling lets analytics load quickly. (Cloudflare Docs)


How to interpret your screenshot

Your data means:

  • None (direct) → ~53k direct visits (estimated)
  • cn.bing.com → ~750 visits (maybe actually ~734–766)
  • /upgrade-claude-code-en → ~430 visits (estimated)

These are trend-accurate, not exact.


When sampling happens

Cloudflare uses sampling when:

  • traffic is high
  • query is complex
  • long time range selected
  • many dimensions (referer + path + UA)

Then it switches to:

  • 100% data (small traffic)
  • 10% data (medium traffic)
  • 1% data (very large traffic)

Bottom line

Yes:

  • “sample by 10%” → Cloudflare only looks at 1/10 of traffic
  • numbers are estimated
  • values often end with 0
  • your interpretation is correct

Your analytics are directionally correct, not precise.