📡 HTTP Cache Header Generator

Visually configure Cache-Control/ETag/Expires cache policies, generate server config code

Zero Dependencies · Works Offline

🎯 Preset Policies

⚙️ Cache Parameters

Cache-Control Directives
max-age (seconds)
≈ 365 days
s-maxage (CDN cache time, seconds, 0=not set)
Validation Method
Resource Type

📋 Cache Policy Evaluation

📄 HTTP Response Headers

🖥️ Server Config Code

What Can the HTTP Cache Header Generator Do?

The HTTP Cache Header Generator is a free online developer tool that helps you visually configure HTTP caching policies. Through an intuitive interface, select Cache-Control directives, validation methods, and cache durations to automatically generate complete HTTP response headers and multi-server configuration code (Nginx/Apache/Node.js/Caddy). Built-in presets for static assets, HTML, API, and more. Real-time policy evaluation. All processing runs locally in your browser—no data is ever uploaded.

Core Features

How to Use

1. Select a preset policy (e.g., "Static Assets") or manually check Cache-Control directives.

2. Set max-age cache duration and validation method (ETag/Last-Modified).

3. Choose resource type and review cache policy evaluation and HTTP response headers.

4. Switch server tabs to copy the corresponding configuration code.

Use Cases

Frontend Deployment Optimization

Frontend engineers configure long-term caching + filename hashing for CSS/JS/images to reduce repeated requests and improve page load speed.

API Cache Strategy

Backend developers set appropriate cache policies for API endpoints, balancing data freshness and server load.

CDN Configuration

Ops engineers configure CDN caching policies using s-maxage to control edge node cache duration.

Technical Background

HTTP caching is a core web performance optimization technology. Browser caching is divided into strong caching (Expires/max-age) and conditional caching (ETag/Last-Modified). During strong cache periods, browsers use local copies without requests; conditional caching requires server validation (304 Not Modified). Cache-Control is the HTTP/1.1 standard with higher priority than HTTP/1.0 Expires. The immutable directive tells browsers the content won't change, eliminating revalidation—especially useful for filenames containing hashes. The Vary header specifies which request headers affect the cache key, commonly Vary: Accept-Encoding for gzip/brotli variants.

❓ FAQ

What are HTTP cache headers?

HTTP cache headers are response fields controlling how browsers and CDNs cache resources. Common ones: Cache-Control, ETag, Last-Modified, Expires.

Common Cache-Control directives?

max-age (duration), no-cache (must validate), no-store (no caching), public/private (scope), must-revalidate, immutable.

ETag vs Last-Modified?

ETag is content-based (hash), precisely detecting changes. Last-Modified is time-based with second precision. ETag is more accurate but slightly costlier.

How to choose cache strategy?

Static assets: long cache + immutable; HTML: no-cache for validation; API: max-age or no-store based on update frequency.

no-cache vs no-store?

no-cache allows caching but requires validation before use (304). no-store completely prohibits caching, always fetching fresh content.

Is data uploaded?

No. All configuration and code generation runs locally in your browser.

HTTP Cache Header Generator | No Signup, Client-Side · No Server Uploads

Feedback: dexshuang@google.com