Cloudflare Cache Tuning¶

Cache Configuration¶

Default Cache Behavior¶

Resource Type	Cache Duration	Cloudflare Default
Static assets (CSS, JS, images)	30 days	Standard
HTML	Bypass (default)	Bypass
API responses	Bypass	Bypass

Enable Cache on HTML¶

Using Cache Rules (recommended for WordPress):

Rule: example.com/wp-content/*.css
Cache Level: Cache Everything
Edge TTL: 7 days

Rule: example.com/wp-content/*.js
Cache Level: Cache Everything
Edge TTL: 7 days

Rule: example.com/wp-content/uploads/*
Cache Level: Cache Everything
Edge TTL: 30 days

Page Rules (Legacy)¶

# Cache static assets aggressively
example.com/wp-content/*:
  - Cache Level: Cache Everything
  - Edge Cache TTL: 7 days

# Bypass admin and login
example.com/wp-admin/*:
  - Cache Level: Bypass
  - Disable Performance: On

example.com/wp-login.php:
  - Cache Level: Bypass
  - Disable Performance: On

# Bypass cart/checkout (WooCommerce)
example.com/cart/*:
  - Cache Level: Bypass

example.com/checkout/*:
  - Cache Level: Bypass

Cache Rules (New)¶

Create a Cache Rule¶

Dashboard → Rules → Cache Rules
Create Rule

Expression:
(starts_with(http.request.uri.path, "/wp-content/"))

Setting: Edge TTL → Override → 7 days
Setting: Cache Level → Override → Cache Everything

Expression:
(starts_with(http.request.uri.path, "/wp-admin/") or starts_with(http.request.uri.path, "/wp-login.php"))

Setting: Cache Level → Override → Bypass

Purge Cache¶

Dashboard¶

Go to Dashboard → Caching → Configuration
Click Purge Everything
Or Custom Purge by URL/path

API¶

# Purge everything
curl -X POST "https://api.cloudflare.com/client/v4/zones/$ZONE_ID/purge_cache" \
  -H "Authorization: Bearer $API_TOKEN" \
  -H "Content-Type: application/json" \
  --data '{"purge_everything": true}'

# Purge specific URLs
curl -X POST "https://api.cloudflare.com/client/v4/zones/$ZONE_ID/purge_cache" \
  -H "Authorization: Bearer $API_TOKEN" \
  -H "Content-Type: application/json" \
  --data '{
    "files": ["https://example.com/css/style.css", "https://example.com/js/app.js"]
  }'

# Purge by tag (if cache tags enabled)
curl -X POST "..." \
  --data '{"tags": ["css", "images"]}'

ARGO¶

Argo routes traffic through the fastest network path.

Enable¶

Dashboard → Speed → Optimization → Argo → Enable

Benefits¶

30% faster load times (Cloudflare claim)
Smart routing around network congestion
Reduced origin server load

Cache Reserve¶

Extends cache to Cloudflare's persistent storage.

# Enable via API
curl -X POST "https://api.cloudflare.com/client/v4/zones/$ZONE_ID/cache/reserve" \
  -H "Authorization: Bearer $API_TOKEN" \
  -H "Content-Type: application/json" \
  --data '{"value": "on"}'

Polish (Image Optimization)¶

Dashboard → Speed → Optimization → Polish → Enable

Mode	Description
Lossless	No quality loss, reduced size
Lossy	Some quality loss, smaller files

Auto Minify¶

Dashboard → Speed → Optimization → Auto Minify

Enable for: JavaScript, CSS, HTML

Brotli Compression¶

Dashboard → Speed → Optimization → Brotli → Enable

Better compression than gzip (20-30% smaller).

Origin Cache Control¶

# In Nginx, respect Cloudflare cache headers
location ~* \.(jpg|jpeg|png|gif|ico|css|js)$ {
    expires 30d;
    add_header Cache-Control "public, immutable";
}

location / {
    # Don't cache HTML by default
    add_header Cache-Control "no-store, no-cache, must-revalidate";
}

Cloudflare Workers (Custom Caching)¶

// Custom cache behavior
addEventListener('fetch', event => {
  event.respondWith(handleRequest(event.request))
})

async function handleRequest(request) {
  const url = new URL(request.url)

  // Cache API responses for 1 hour
  if (url.pathname.startsWith('/api/')) {
    return fetch(request, {
      cf: {
        cacheTtl: 3600,
        cacheEverything: true,
      }
    })
  }

  return fetch(request)
}

Cache Analytics¶

Monitor cache performance:

Dashboard → Analytics & Logs → Cache
Hit ratio — percentage served from cache
Bandwidth saved — origin offload
Top uncached URLs — what to add to cache rules