Compute SHA-3 (Keccak) digests.
SHA-3 Hash is a small tool that does one job while you watch. Nothing is saved, so a reload gives you a clean start.
Load the page once and it works offline from then on. Nothing about the tool needs a connection after that first request.
You will find it under Hashes, alongside 15 other tools for the same sort of job.
Supports SHA3-256 and SHA3-512 variants with hex output.
hello
3338be694f50c5f338814986cdf0686453a888b84f424d792af4b9202398f392
Yes. It is JavaScript running in this tab, so once the page has loaded it needs nothing further from the network. Put the machine in flight mode and it carries on. Nothing you do here is sent anywhere, because there is nowhere for it to go.
No. Reload the page and it starts from nothing. There is no account, no saved state and no cookie holding your last session. That is a deliberate trade: it cannot lose your data because it never keeps any.
Timing comes from performance.now(), the high resolution clock the browser provides, rather than from setInterval, which drifts by a few milliseconds every tick and compounds over minutes. What can still shift things is the browser throttling a tab in the background, so leave it visible if the timing matters.
Where a sound makes sense, it is generated with the Web Audio API rather than loaded as a file, so there is nothing to download and nothing to block. Browsers refuse to start audio until you have interacted with the page, which is why the first press is what switches it on.
Yes. The controls are sized for touch and the layout collapses to one column on a narrow screen. Bear in mind that a phone locking its screen will suspend the page, and timing stops with it.