What is TTFB and why does it matter?

TTFB (Time to First Byte) is the time from when the browser sends a request to when it receives the first byte of the response. It measures server processing time excluding network transfer. For users in India, a high TTFB from a server hosted only in the US can add 200–400ms to every page load.

Why is my site slow in Australia but fast everywhere else?

This is usually caused by CDN misconfiguration, missing POPs in the APAC region, or a server located in the US without edge caching. The Latency Detector shows exactly which phase (DNS, TCP, TLS, or server processing) is adding the delay in each region.

What latency is considered good?

Under 100ms TTFB is excellent. 100–300ms is acceptable. Over 300ms degrades user experience measurably. For API endpoints used by mobile apps, under 200ms total response time is the industry target.

Free Tool — 6 Probe Regions

Free Global Latency Detector

Measure detailed latency from selected probe regions. See DNS resolution, TCP handshake, TLS negotiation, and TTFB broken down clearly.

This website latency test tool measures response performance from multiple regions so teams can diagnose where real users experience delay. It helps isolate bottlenecks in routing, edge configuration, TLS negotiation, and backend response paths. Single-location tests cannot reveal these differences, which makes region-aware latency testing essential for global products. Engineering teams use this to prioritize performance fixes by customer impact and validate optimization outcomes after infrastructure changes.

What this tool detects

Region-specific latency degradation
Edge and network delay patterns
Performance regressions after deploys

Q: Which latency metric should I optimize first?

A: Start with end-to-end regional response time, then break into DNS, TCP, TLS, and server phases to identify the dominant bottleneck.

Probe from3/3 selected(max reached)

What We Check

1
Enter URL or endpoint — Enter your URL or API endpoint.
2
Run selected probe checks — Latency checks run for your currently selected probe regions.
3
DNS resolution time — DNS resolution time measured per region.
4
TCP connection time — TCP connection time measured per region.
5
TLS negotiation time — TLS negotiation time measured per region.
6
TTFB measurement — Time to First Byte (TTFB) measured per region.
7
Total response time — Total response time measured per region.
8
Latency heatmap — Latency heatmap generated showing fastest and slowest regions.

FAQs

What is TTFB and why does it matter?: TTFB (Time to First Byte) is the time from when the browser sends a request to when it receives the first byte of the response. It measures server processing time excluding network transfer. For users in India, a high TTFB from a server hosted only in the US can add 200–400ms to every page load.
Why is my site slow in Australia but fast everywhere else?: This is usually caused by CDN misconfiguration, missing POPs in the APAC region, or a server located in the US without edge caching. The Latency Detector shows exactly which phase (DNS, TCP, TLS, or server processing) is adding the delay in each region.
What latency is considered good?: Under 100ms TTFB is excellent. 100–300ms is acceptable. Over 300ms degrades user experience measurably. For API endpoints used by mobile apps, under 200ms total response time is the industry target.

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