Performance

CDN Caching Strategy with Cloudflare

Author :Liam K.
Date :March 08, 2026
Time :14 minutes

Caching Model

Split content into immutable static assets, short-lived HTML, and no-cache private/API responses.

Step 1: Set Origin Cache Headers

http

# Static assets (hashed filenames)
Cache-Control: public, max-age=31536000, immutable

# HTML pages
Cache-Control: public, max-age=60, s-maxage=300, stale-while-revalidate=120

# API/private content
Cache-Control: no-store

Step 2: Nginx Header Example

nginx

location ~* \.(css|js|png|jpg|jpeg|gif|svg|webp|woff2)$ {
    add_header Cache-Control "public, max-age=31536000, immutable";
}
location / {
    add_header Cache-Control "public, max-age=60, s-maxage=300, stale-while-revalidate=120";
}
location /api/ {
    add_header Cache-Control "no-store";
[...]

Command truncated. Copy to view full command.

Step 3: Cloudflare Recommended Settings

Caching: Standard
Browser Cache TTL: Respect Existing Headers
Always Use HTTPS: On
Auto Minify: JS/CSS/HTML as needed

Step 4: Cache Rules

text

Rule 1: If URI path matches /assets/*
Action: Cache eligibility = Eligible
Edge TTL: 1 month
Browser TTL: Respect origin

Rule 2: If URI path matches /api/*
Action: Cache eligibility = Bypass cache

Step 5: Purge Strategy

Prefer versioned asset filenames and only purge HTML on release.

bash

curl -X POST "https://api.cloudflare.com/client/v4/zones/$ZONE_ID/purge_cache"   -H "Authorization: Bearer $CF_API_TOKEN"   -H "Content-Type: application/json"   --data '{"files":["https://example.com/","https://example.com/pricing"]}'

Step 6: Validate Cache Behavior

bash

curl -I https://example.com/
curl -I https://example.com/assets/app.abc123.js

Look for headers such as cf-cache-status: HIT, cache-control, and correct content variation behavior.

Step 7: Avoid Common Mistakes

Never cache authenticated API responses unless explicitly segmented by key.
Avoid long TTL on unversioned assets.
Do not purge entire zone on every deploy.

"Good caching strategy is a release strategy. The CDN amplifies whatever discipline your deploy process has."

Technical Author

Liam K.

System administrator and technical writer specializing in server infrastructure, security and deployment. Creating comprehensive guides to help you master server administration.