Tag
Performance
Improve HTTP delivery with caching, compression, connection reuse, timing signals, and response metadata. This curated hub brings together 24 related resources.
- HTTP Status Codes
103 Early Hints
The server sends preliminary response headers to help the client start preloading resources. Learn how 103 Early Hints improves page load performance.
- HTTP Status Codes
304 Not Modified
Cached response is still valid. Learn how 304 Not Modified improves performance through conditional requests and caching.
- Comparisons
304 Not Modified vs 200 OK
Understand when servers return 304 Not Modified instead of 200 OK. Learn how conditional requests, ETags, and Last-Modified headers enable efficient HTTP caching.
- HTTP Headers
Accept-Encoding Header
Learn how Accept-Encoding tells servers which compression formats (gzip, br, deflate) your client supports to reduce bandwidth and speed up page loads.
- HTTP Headers
Access-Control-Max-Age Header
Learn how Access-Control-Max-Age specifies how long browsers can cache CORS preflight results. Reduce preflight requests and improve cross-origin performance.
- HTTP Headers
Cache-Control Header: Directives, Examples and CDN Behavior
Cache-Control directives explained: max-age, no-cache vs no-store, s-maxage, stale-while-revalidate, immutable, with nginx, Cloudflare and Next.js examples.
- Comparisons
Cache-Control: no-cache vs no-store
Compare the no-cache and no-store Cache-Control response directives and choose the correct policy for sensitive or frequently changing responses.
- Glossary
CDN (Content Delivery Network)
A CDN is a network of edge servers that cache and serve responses near users. See how cache hits show up in headers and what CDNs do not cache by default.
- HTTP Headers
Content-Encoding
Learn how Content-Encoding specifies compression algorithms (gzip, br, deflate) used to encode response bodies. Reduce bandwidth and improve load times.
- HTTP Headers
Early-Hints
Learn how 103 Early Hints allows servers to send preload hints while preparing the main response. Improve page load performance with early resource loading.
- Guides
HTTP Compression: gzip, Brotli and Zstandard Setup
How HTTP compression works: Accept-Encoding negotiation, gzip vs Brotli vs zstd, nginx, Caddy, Express and Cloudflare config, BREACH, and measuring with curl.
- Guides
HTTP Headers and Caching: A Practical Guide
Master HTTP caching with Cache-Control, ETag, Last-Modified, and conditional request headers. Learn how to optimize performance with proper cache strategies.
- Guides
HTTP Range Requests: 206, Resume and Video Seeking
How HTTP range requests work: Range, Accept-Ranges, 206 and Content-Range, multipart/byteranges, 416, If-Range for safe resumes, and CDN and compression traps.
- Comparisons
HTTP/1.1 vs HTTP/2
Compare HTTP/1.1 and HTTP/2. Understand multiplexing, header compression, server push, and when upgrading to HTTP/2 actually improves performance.
- Comparisons
HTTP/2 vs HTTP/3: TCP, QUIC and Fallback
Compare HTTP/2 over TCP with HTTP/3 over QUIC: packet loss, stream blocking, connection migration, 0-RTT replay, discovery and curl fallback checks.
- Guides
HTTP/3 and QUIC Explained: Setup, Fallback, 0-RTT
How HTTP/3 and QUIC work: UDP/443, connection IDs, 0-RTT replay risk, Alt-Svc and HTTPS DNS record discovery, nginx/Caddy/Cloudflare setup, and curl checks.
- Glossary
Keep-Alive (Persistent Connections)
Keep-alive reuses one TCP connection for many HTTP requests. Learn the HTTP/1.1 default, idle timeout defaults in nginx and Node, and why mismatches cause 502s.
- HTTP Headers
Keep-Alive Header
Learn how the Keep-Alive header controls HTTP connection persistence and reuse. Reduce latency and improve performance by avoiding repeated TCP handshakes.
- HTTP Headers
Link Header
Learn how the Link header provides resource hints and enables preloading of CSS, fonts, and scripts to improve page load performance and user experience.
- HTTP Headers
Performance-Timing: Server-Timing, Timing-Allow-Origin and Performance APIs
There is no Performance-Timing HTTP header. Use Server-Timing, Timing-Allow-Origin, the Navigation and Resource Timing APIs, TTFB and INP instead.
- HTTP Headers
Server-Timing Header
Learn how the Server-Timing header communicates server-side performance metrics to browsers. Analyze backend timing, database queries, and optimize performance.
- HTTP Headers
Timing-Allow-Origin
Learn how the Timing-Allow-Origin header specifies which origins can access Resource Timing API data. Enable cross-origin performance monitoring securely.
- Glossary
TTFB (Time to First Byte)
TTFB is the time from starting a request until the first byte of the response arrives. Learn what it includes, how to measure it and what usually inflates it.
- HTTP Headers
X-Response-Time
Learn how the X-Response-Time header indicates server processing time in milliseconds. Useful for performance monitoring and debugging slow requests.