About nyaa.tools
52 small tools that run in a browser tab. No accounts, no uploads, no ads.
Most of what a developer needs during a day is small: decode a token, check why mail is bouncing, work out what a cron line means, tell whether a DNS change has landed yet. The usual answer is whichever site ranks first, which typically means an ad-funded page that wants the thing you pasted more than it wants to help you. nyaa.tools is the other option: the same utilities, computed where you are.
The rule
Every claim on this site has to be exactly true. That sounds obvious and it is mostly a constraint on what can be said, not on what can be built. Some things it has cost:
- The IP tool does not report VPN or proxy detection. Those signals only exist in MaxMind's more expensive Insights service; this site uses City, where the field would always read "false" — a confident answer that means nothing.
- The hash tool labels its fifth digest Keccak-512, not SHA-3. NIST changed the padding when
it standardised Keccak, so the two produce different output and calling it SHA-3 would not
match what
opensslgives you. - The homepage says "44 of 52 run fully offline" rather than "everything runs in your browser", because eight tools do reach the network and a blanket claim with an exception is just a false claim.
- The DNS propagation checker will not tell you a change has not propagated when the real answer is that the domain is behind a load balancer handing out different addresses on purpose. It distinguishes the two and says which it thinks it is seeing.
How it works
44 of the 52 tools compute entirely in the page and send nothing anywhere. That is not a policy, it is the architecture: the code that formats your JSON is running in your tab, so there is no server to send it to. You can paste a production token into the JWT decoder or a private key into the checksum tool and watch the network panel stay empty.
The eight that do use the network say so on their card and inside the tool, and they fall into two kinds. The DNS, WHOIS, ASN and propagation tools query public providers directly from your browser, so the lookup goes where your DNS traffic already goes and nyaa.tools never sees it. IP geolocation and currency rates go through this site's own API, because both come from licensed providers whose keys cannot be published in a browser bundle. The privacy page sets out exactly what that means, including what is stored and for how long.
Built the boring way
- Every tool is a separate lazily-loaded chunk, so the landing page costs 9 requests and 89 kB and you only download the tool you open.
- Each tool is also a real, pre-rendered page, so it works with JavaScript disabled long enough to read what it does, and crawlers get content rather than an empty div.
- The logic that is easy to get quietly wrong — unbiased random draws, GS1 check digits, affine temperature conversion, Morse timing, MAC registry lookups, JSON error positions — is kept in plain modules with 518 assertions over them, because "it looked right" is not a test.
- Any tool can be embedded in your own docs or wiki. Open one and press
</> Embedfor the snippet.
Who
A one-person project, built because these were the tools its author kept googling. It is free, it has no business model, and nothing on it is for sale.