A growing set of small, privacy-conscious developer utilities. Most run entirely in your browser.
.env Comparator
Spot missing, extra, or changed keys between two env files — without leaving your browser.
- DevOps
CIDR / Subnet Calculator
Break a CIDR into its network, broadcast, range, masks, and a coloured binary view.
- Networking
- DevOps
Semver Range Tester
Test a semver range against a list of versions — see which match, and which comparator group caught them.
- DevOps
Docker Run to Compose
Paste a docker run command, get a docker-compose service snippet — with warnings for anything that doesn't translate cleanly.
- DevOps
JWT Decoder
Decode a JSON Web Token's header and payload in your browser. No signature verification, no network call.
- Security
Unix Timestamp Converter
Convert between Unix timestamps and human-readable dates. Auto-detects seconds vs milliseconds.
- Dates
Epoch Converter
Convert in either direction — Unix epoch (seconds or milliseconds) to a datetime, or a date/time picker back to an epoch.
- Dates
SHA Hash Generator
Compute SHA-1, SHA-256, SHA-384, and SHA-512 digests of arbitrary text. Hex + base64, instant.
- Security
UUID / GUID Generator
Generate v4 (random) or v5 (name-based) UUIDs — Microsoft GUIDs are the same format. Formatting toggles for case, braces, and hyphens.
- Identifiers
Cron Tester
Parse and describe cron expressions in plain English. Supports standard (5-field) and Quartz / Azure Functions (6-field with seconds).
- DevOps
Unicode Inspector
Break a string down by Unicode codepoint, UTF-8 bytes, UTF-16 units, and HTML entity. Find invisible characters and encoding glitches.
- Text
Text to List
Turn a line-separated list into SQL, JSON, JS, Python, CSV, YAML, Markdown, HTML and more — quoted and escaped correctly.
- Text
Chmod Calculator
Convert between octal (755) and symbolic (rwxr-xr-x) Unix file permissions. Click the matrix or paste a value.
- DevOps
robots.txt Validator
Parse a robots.txt, surface syntax issues, and test whether a path is allowed or blocked for a given user-agent.
- DevOps
CSP Builder
Compose a Content-Security-Policy header directive-by-directive. Quotes keywords automatically, lints risky combinations, emits header + meta-tag.
- Security