Cache health
Read the dashboard: warmth score, cache hits, cold URLs, and how much faster warming made your site.
9 min read
Warming without measurement is guesswork. Cache health turns every warm run into a picture of what is actually cached, what stays cold, and how much faster warming made things.
It is the landing page of your account, under Account → Cache health.
Note
The page is empty until a warmer has run at least once. If you see “No crawl data yet”, start a warmer and come back.
The headline figures
- Warmth score
- The share of tracked URLs that look properly cached, based on response timings and cache-related headers. The single best number for “is this working?”. Watch its direction over time more than its absolute value.
- URLs tracked
- How many distinct URLs have crawl data. If this is far below your real page count, your warmers are not covering the site — check depth, sitemaps, and exclusions.
- Cache hits
- How many URLs showed a cache hit, with cold and unknown counted separately. “Unknown” simply means your CDN did not send a header Cache Rocket could read; it is not a failure.
- Average improvement
- The mean gap between first load and warm load. This is warming's return on investment, expressed in time saved for real visitors.
- Detected cache providers
- Which CDN or cache layers were identified from response headers. Useful confirmation that traffic is going through the CDN you think it is.
By hostname
The same figures, broken down per hostname. This is where agencies and multi-site owners spend their time — one client's site can be perfectly warm while another quietly fails, and the account-wide average hides it.
Compare average load times between hostnames. A consistent outlier usually points at hosting or caching configuration rather than anything about warming.
Cold and slow URLs
The most actionable list on the page: URLs that stay slow even after being warmed. This almost never means warming failed — it means those URLs are not being cached in the first place.
Common reasons a URL stays cold:
| Cause | How to check | Fix |
|---|---|---|
| Response says not to cache | Look for Cache-Control: no-store or private in the response headers | Change the caching rules for that route |
| The page sets a cookie | Look for a Set-Cookie header on a page that should be anonymous | Stop setting session cookies on public pages, or configure the cache to ignore them |
| The route is genuinely personalised | Cart, account, checkout, dashboard | Nothing to fix — exclude it from the warmer |
| The CDN is bypassed for that path | Check your CDN's page or cache rules | Adjust the rule so the path is cached |
| The page is just slow to build | Both first and warm load are high | An application performance problem; warming cannot mask it |
Tip
Work this list from the top. Fixing the cacheability of a handful of high-traffic routes usually moves the warmth score more than any amount of warmer tuning.
Best improvements and slowest URLs
Best warm improvements shows where warming saved the most time. This is your evidence — the concrete answer to “is this worth paying for?”, and the numbers to put in a report to a client or manager.
Slowest URLs ranks by absolute response time. These are your application performance problems. Warming hides the cost from most visitors, but the underlying page is still expensive, and it is still slow for the warm run and for anyone who misses cache.
A weekly routine
- 1
Check the warmth score direction
Trending up or holding steady is fine. A drop means something changed — a deploy, a CDN rule, or a warmer that stopped.
- 2
Confirm URLs tracked still matches your site
A sudden fall means coverage broke. A sudden rise may mean a new URL family is being discovered that you should exclude.
- 3
Work the top of the cold URLs list
Fix one or two cacheability problems. This is where the real gains are.
- 4
Glance at slowest URLs
Feed genuinely slow pages back to whoever owns application performance.
- 5
Note the average improvement
Track it over time. It is the cleanest single measure of value delivered.
Common questions
- My warmth score is lower than I expected. Is warming broken?
- Usually not. A low score most often means part of your site is not cacheable — personalised routes, cookie-setting pages, or CDN bypass rules. Check the cold URLs list before touching warmer settings.
- Many URLs show “unknown” rather than hit or miss.
- Your CDN is not returning a cache-status header Cache Rocket recognises. That is a reporting gap, not a caching failure — the load-time improvement figures are still meaningful.
- Does cache health need a specific CDN?
- No. It works from warm-run outcomes and response headers on any stack. CDN integrations add purge and rewarm on top, but are not required for health reporting.
- Why is average improvement small on some sites?
- Either your pages were already fast to build, so there was little to save, or they were already warm from real traffic. Both are good outcomes.
- Health looked fine yesterday and is bad today.
- Something changed. Check for a recent deploy, a CDN configuration change, an expired API key breaking a webhook, or a warmer that was switched off. Set up Alerts so you hear about this without checking manually.