Security
Security-related tools such as hashing, inspecting JWT contents and generating passwords. All input is processed in your browser and never sent to a server.
11 tools・Ordered by measured page views over the last 90 days.
Password Generator
Generate strong random passwords with a secure RNG; choose length and character types, then copy.
Hash Generator (SHA)
Compute SHA-1/256/384/512 hashes from text in the browser via Web Crypto.
SRI Hash Generator
Build the integrity attribute for a CDN file, with sha256, sha384, sha512 and a ready tag.
HMAC Calculator
Compute HMAC-SHA-1/256/384/512 from a message and a shared secret, shown in hex and Base64, with a match check against a signature you received. Useful for verifying webhook signatures. Runs in the browser.
JWT Decoder
Decode a JWT's header and payload and pretty-print claims like exp.
Find the Source of a Hash
Find the value behind a hash by candidate-list matching or a constrained pattern search. SHA family, CRC32 and FNV-1a. Runs in your browser.
Basic Auth Header Generator
Build an Authorization: Basic header from a user name and password, with curl and fetch snippets, and decode Basic strings back.
Email Header Analyzer
Paste raw email headers to get the Received chain in delivery order with per-hop delays, the SPF, DKIM and DMARC results, and every header unfolded. Decodes RFC 2047 subjects. Runs in the browser.
SPF / DMARC Record Checker
Breaks an SPF or DMARC TXT record into terms with explanations, counts how much of the RFC 7208 ten DNS lookup budget it spends, and flags risky settings such as +all and ptr. No DNS queries.
Set-Cookie Analyzer
Break a Set-Cookie header into attributes and find every reason a browser would reject the cookie.
CSP Header Builder
Assemble a Content-Security-Policy header and meta tag from per-directive sources. Repairs missing quotes and warns about gaps like frame-ancestors and base-uri.