Developer Tools That Never Leave Your Browser

Compute MD5, SHA-1, SHA-256, SHA-384, SHA-512, CRC32 and HMAC-SHA256 digests from text or a local file. Runs entirely in your browser.

Encode text, files and images to Base64 or decode Base64 back to text, in both the standard and URL-safe alphabets. Includes a live image preview and data-URL builder.

Percent-encode URLs, query strings and path segments to RFC 3986, escape or unescape HTML entities, and preview the result as rendered markup.

Encrypt and decrypt text with AES-GCM, AES-CBC, Triple DES and RSA-OAEP using the browser's native Web Crypto API. Keys and plaintext never leave the page.

Decode and inspect JSON Web Tokens: header, payload and signature, with expiry countdown, claim explanations and optional HMAC or RSA signature verification.

Beautify, minify and validate JSON with precise error positions, a collapsible tree view, JSONPath queries and key statistics. Nothing is uploaded.

Convert between JSON, YAML, TOML, XML, CSV and INI in any direction, with comment handling, type inference and a round-trip preview.

Turn a JSON sample into typed TypeScript interfaces, Go structs, Java classes, Python dataclasses, Rust structs, JSON Schema or SQL DDL, with nullability inferred from the data.

Test regular expressions against sample text with live highlighting, capture-group inspection, replace preview and a plain-language explanation of the pattern.

Compare two blocks of text and see every addition and deletion, in unified or side-by-side view, at character, word or line granularity, with intra-line highlighting.

Count characters, words, sentences, paragraphs and UTF-8 bytes, measure reading and speaking time, chart word frequency, and convert between nine naming conventions.

Write Markdown with a live preview, a toolbar, an outline and statistics, then export as Markdown or sanitised HTML. Rendering happens entirely offline.

Generate UUID v1, v4 and v7, ULIDs, Nano IDs, ObjectIds and random passwords in bulk, with entropy figures and collision-probability estimates.

Break a URL into protocol, host, port, path, query and fragment, edit query parameters in a table, and rebuild the URL — with percent-decoding and duplicate-key detection.

Decode a User-Agent string into browser, engine, operating system, device type, CPU architecture and bot status, with a full token breakdown.

Convert Unix timestamps to dates and back, in seconds or milliseconds, across every timezone, with ISO 8601, RFC 2822, relative time and week-number output.

Calculate the days, weeks, months and years between two dates, add or subtract durations, work out an exact age, and count business days excluding weekends and holidays.

Calculate hours worked between start and end times, across multiple rows, with break deduction, rounding, overnight shifts, overtime rates and CSV export.

Convert between binary, octal, decimal, hexadecimal and any base up to 36, with arbitrary precision, two's complement, bit-level views and IEEE-754 float decoding.

Explain a cron expression in plain language and see the next scheduled run times, in any timezone, with DST warnings and a full field-by-field breakdown.

Convert and compress images between JPEG, PNG, WebP and AVIF, with resizing, rotation, quality control and before-and-after size comparison, all locally.

Minify and optimise SVG files by stripping editor metadata, comments, default attributes and unused ids, rounding coordinates and reporting both raw and gzipped savings.

Create QR codes for text, URLs, Wi-Fi credentials, vCards, email, SMS, locations and calendar events, with error correction, logo overlay and PNG or SVG export.