Developer

Format and validate JSON. Indented or minified output, with clear error messages.

Encode text to Base64 or decode Base64 back to text. UTF-8 safe.

Percent-encode or decode URL components.

Decode JWT header and payload locally. Signature is not verified — paste tokens at your discretion.

Generate random UUIDs (v4) in your browser. Bulk generation up to 100 at a time.

Generate MD5, SHA-1, SHA-256, and SHA-512 hashes from text. Runs entirely in your browser.

Convert between JSON and YAML in either direction. Clear error messages with line numbers.

Check YAML syntax and surface every error with line and column. Built for k8s, GitHub Actions, and CI configs.

Test JavaScript regular expressions against text. See every match, capture groups, and flag effects in real time.

Compare two texts side by side. Line, word, or character-level diff with clear highlighting.

Encode reserved HTML characters to entities, or decode entities back. Optional escape for all non-ASCII.

Parse a URL or query string into key/value pairs, edit them, and rebuild a clean query string.

Convert between Unix timestamps and ISO 8601 dates. Local and UTC views with relative time, instant updates as you type.

Live Markdown editor with side-by-side preview. GitHub-flavored Markdown, autosave, and HTML/MD download.

Calculate IPv4 and IPv6 subnets — network, broadcast, host range, mask, and usable host count from a CIDR.

Convert between CSV and JSON, both directions. RFC 4180 parsing handles quoted fields and embedded newlines; delimiter and header options are configurable.

Searchable HTTP status code reference (1xx → 5xx) with short descriptions and typical use cases. Filter by class, copy a code, link to the IETF spec.

Validate a 5-field cron expression and preview the next N execution times, or build one from a frequency picker (minute/hour/day/week/month/year).

Format SQL queries across major dialects — PostgreSQL, MySQL, Snowflake, T-SQL, BigQuery, SQLite, and more. Keyword casing and indentation are configurable.

Validate a JSON document against a JSON Schema (Draft 2020-12 by default). Errors point to the failing path with a human-readable reason — fully client-side via Ajv.

Paste a curl command and get the equivalent fetch, axios, Go net/http, and Python requests snippet. Handles -X, -H, -d / --data, -u, --form, and multiline backslash continuation.

Drop an AWS Cost Explorer CSV export and see service / region / tag breakdowns, top spenders, month-over-month change, and a plain-language summary. Files never leave your browser.