Web Page Load Time Estimator

Summary

Estimate web page load time from page size and connection speed, with DNS/TCP/TLS overhead, TTFB, and per-asset breakdown.

How it works

1. Enter total page size in KB or MB, or break it down by HTML, CSS, JS, and images.
2. Select a connection preset (2G through gigabit) or enter a custom download speed.
3. Set latency (RTT) for the connection — presets fill this automatically.
4. The tool calculates DNS lookup, TCP handshake, TLS handshake, TTFB, and transfer time.
5. A performance rating (Fast / Moderate / Slow / Very Slow) appears based on total load time.

Use cases

• Set page weight budgets before building a new feature.
• Explain to stakeholders why a 5 MB page loads slowly on mobile.
• Compare estimated load time across connection types for a given page size.
• Sanity-check third-party asset impact before adding a new library.

Frequently Asked Questions