Bulk TTFB & Speed Checker
Time to first byte is the moment a browser receives the first byte of the response: it includes the DNS lookup, the TCP connection, the TLS handshake and the server thinking time before it starts sending the page.
More about this tool
Search engines use TTFB as a crawling efficiency signal, and users feel it as the delay before anything appears at all. This bulk checker measures TTFB for a whole list of URLs in parallel, together with the total response time, the HTML size in bytes and kilobytes, the number of redirects on the way and the final URL each address settles on. Every URL gets a simple speed grade from A to F so you can scan the report top to bottom and instantly see the slowest pages; values above your own threshold are highlighted. It is a practical tool for comparing hosting options, tuning caches, verifying that a new server or CDN actually made pages faster, and spotting the odd slow page in a large section. Requests are made over HTTPS with browser-like headers, and the report exports to CSV for further analysis.
How it works
- Paste up to 100 items, one per line. Duplicates are removed automatically.
- URLs without a scheme are checked over https://.
- The check runs in the background; the results page shows live progress.
- Filter the report by status code and export it to CSV.
Rate limit: 5 jobs per hour from one IP address. Results are stored for 7 days.
FAQ
What exactly is TTFB?
Time to first byte: the full delay from starting the request to receiving the first byte of the response — DNS, TCP connect, TLS handshake and the server generating the page. Each URL here is measured over a fresh connection, the way a first-time visitor or a search bot experiences it.
How is the A–F grade calculated?
By TTFB: A is under 200 ms, B under 500 ms, C under 800 ms, D under 1500 ms, and everything slower gets an F. The thresholds follow common field-data buckets; adjust the highlight threshold in the form to your own standard.
Why is total time larger than TTFB?
Total time also includes downloading the HTML itself (plus any redirect hops), while TTFB is measured at the first byte. The gap between the two shows how big the document is and how fast the connection streams it.
Can I compare hostings with this?
Yes — run the same URL list before and after a migration and compare the two CSV exports. Keep in mind that a single measurement has natural jitter: for important comparisons run the check a couple of times and look at the consistent difference, not one-off values.
Does the checker download the whole page?
It downloads the HTML document (up to 256 KB — enough for virtually any page) but not images, styles or scripts. The size column therefore reflects the HTML itself, which is what matters for caching and template weight decisions.
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