tools
Small utilities that run in your browser: no server, no accounts.
- Password Generator · Generate a random password or a word-based passphrase in your browser.
- Dig over DoH · Client-side DNS-over-HTTPS lookup.
- Subnet Calculator · Work out a network, broadcast, netmask, host range, and host count from an IPv4 or IPv6 CIDR.
- X.509 Certificate Analyzer · Decode a PEM/DER certificate: subject, issuer, validity, serial, and SANs.
- Multi-Encoder · Encode text in fourteen encodings at once, or decode a pasted value back into text.
- Email Header Analyzer · Trace an email's Received hops with delays, and read its auth (SPF/DKIM/DMARC) results.
- HTTP Response Header Analyzer · Paste HTTP response headers and grade the recommended security set.
- CVSS Calculator · Score a CVSS v3.1 or v4.0 vector: the score, its severity band, and the vector string.
- File Hasher & Checksum Verifier · MD5, SHA-1, SHA-256, SHA-512 and BLAKE3 of text/local files, and a checksum verifier.
- Hashprint Codec · Draw a SHA-256 or SHA-512 digest as a grid that decodes back to it, and compare two cell by cell.
- JWT Decoder · Decode a JWT's header and payload locally, and verify the signature when you supply a key.
- Log Parser · Pretty-print JSON logs and parse Common Log Format access lines into fields.
- Regex Reference · Look up a ready-made regular expression: 99 patterns with what each one matches.
- Packet Analyzer · Decode a raw hex packet into an Ethernet / IPv4 / TCP-UDP protocol tree.
- Local HTTP Request Constructor · Build an HTTP request, classify its headers, and generate curl / fetch / reqwest code.
- Epoch Converter · Convert a Unix timestamp to a calendar date in UTC or a named timezone (ISO 8601, weekday, hex).
- chmod Visor · Read and edit a Unix file mode as a grid, octal or symbolic, with alerts on risky modes.
- nmap Builder · Assemble an nmap scan command from options, with a note on how loud it is.
- openssl Helper · Build the openssl command for common certificate and key operations.
- wget Builder · Assemble a wget site-mirror / download command from options.
- Crontab Builder · Explain a cron expression in plain language, or build one from fields or a phrase.
- SSH Config Assistant · Build a ~/.ssh/config Host block from a few connection options.
- File Header Forensics · Identify a file from its bytes, audit its extension against them, and read the header.
- Base Converter · Convert an integer between binary, octal, decimal, and hex.
- Unicode Inspector · Break text into per-character codepoint, UTF-8 bytes, and category.
- Text Width · A string's byte, scalar, grapheme and terminal-width counts, on a column grid.
- Binary Value & Endianness Inspector · Interpret a byte buffer across endianness.
- Terminal Theme & ANSI Palette Designer · Import, validate, preview, and convert colour themes between emulator formats.
- ASCII & Unicode Diagram Studio · Redraw a pasted ASCII diagram in a Unicode connector style, then export it.
- Colour-Contrast & Terminal Readability Checker · WCAG 2 contrast and APCA for two colours, an ANSI palette, or the xterm-256 cube.
- Aspect-Ratio Visualizer · Compare source vs target aspect ratios: letterbox, pillarbox, crop, and stretch.
- Display Planner · Compare monitors on PPI, physical size, FOV, and pixels-per-degree across a multi-monitor desk.
- Display Calculator · Simplify a screen's aspect ratio and compute its pixels-per-inch.
- Keyboard Tester · Sweep your own keyboard for dead switches across ten enthusiast form factors.
- Client-Side Grep & Search · Line-level search over this site's content index, deep-linked to the page.
- Markdown Editor · Write Markdown with a live HTML preview and build the post's frontmatter.