Reduce Time to First Byte (TTFB)
SkillDev toolsttfb is a skill for auditing slow first responses on SSR pages, APIs, or cacheable HTML. It helps your agent measure why a web page or API responds slowly and separate server time from network delays. Use it to distinguish origin compute time from network latency and CDN cache misses before proposing a fix.
Use Reduce Time to First Byte (TTFB) in Claude, ChatGPT or Ahel Desktop
Free. Sign in, add Reduce Time to First Byte (TTFB) and connect your AI. About a minute.
Also: Claude Code · Cursor · Codex
Then ask your AI: use the Reduce Time to First Byte (TTFB) skill
Details
Instructions available. Your AI can read the instructions. Execution depends on the setup they require.
Account requirements not reviewed. Check the skill instructions before use; ahel provides instructions and does not run this skill.
No other account needed.
Have an AI agent that can run skills.
What your AI can do with it
- Measure time to first byte for SSR pages, APIs, and cacheable HTML
- Separate origin compute time from network latency
- Identify CDN cache misses affecting first response
- Audit slow first responses before proposing a fix
Getting started
- Have an AI agent that can run skills.
- Add the ttfb skill to your agent's available skills.
- Point the agent at a URL or endpoint with a slow first response.
- Ask the agent to audit the first response time using ttfb.
What this skill tells your AI
The instructions your AI receives, as published by thedaviddias/front-end-checklist in skills/ttfb/SKILL.md and read by ahel’s review.
TTFB is the foundation of page performance; if the server is slow to respond, all subsequent loading stages are delayed.
Quick Reference
- Optimize server-side logic and database queries to speed up response generation
- Use a Content Delivery Network (CDN) to serve content closer to users
- Implement effective caching strategies at the server and edge levels
Check
Review the page's TTFB and identify any bottlenecks in the server-side processing or network transmission.
Fix
Optimize the server's response time by improving database queries, caching responses, and using a CDN.
Explain
Explain how TTFB impacts the entire page load process and why it is a critical starting point for performance optimization.
Code Review
Review server-rendered routes, API handlers, cache configuration, and database access on the critical path. Flag uncached HTML, slow synchronous work before the first byte, repeated upstream fetches, or expensive queries that keep TTFB above roughly 800ms.
For full implementation details, code examples, and framework-specific guidance,
see references/rule.md.
Rule page: https://frontendchecklist.io/en/rules/performance/ttfb
Signals
- GitHub stars
- 74k
- Forks
- 7k
- Last commit
- Oct 2026
- Hacker News mentions
- 2
Questions
- What does ttfb measure?
- It measures time to first byte for SSR pages, APIs, or cacheable HTML, separating origin compute time from network latency and CDN cache misses.
- When should I use ttfb?
- Use it when auditing slow first responses on SSR pages, APIs, or cacheable HTML, before proposing a fix.
- Does ttfb propose fixes?
- No, it helps distinguish origin compute time from network latency and CDN cache misses before proposing a fix.
- Can ttfb measure client-side rendering?
- No, it focuses on first responses for SSR pages, APIs, or cacheable HTML.
Advanced
- Item type
- skill
- Key
ttfb- Source
- github.com/thedaviddias/front-end-checklist
github.com/thedaviddias/front-end-checklist