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Type any cron expression and get instant validation. Each field (minute, hour, day, month, weekday) is colour-coded for fast visual parsing.

Converts your cron into a human-readable sentence — 'Every 5 minutes, every hour, every day' — using the cronstrue library.

Shows the next 8 upcoming run times in your local timezone so you can verify the schedule is exactly what you intend.

Every minute, every 5 minutes, daily 9am, weekdays 9am, monthly 1st, and more — click to load instantly.

Export to Node.js, Python, Linux crontab, GitHub Actions, and Docker in one click.

The cron expression is encoded in the URL: /tools/cronbuilder?cron=*/5+*+*+*+*

Minute

0–59

Hour

0–23

Day

1–31

Month

1–12

Weekday

0–7

Every character in your pattern is tokenized and colour-coded — literals (green), escapes (teal), quantifiers (orange), anchors (purple), groups (blue), meta (red). Click any token for a plain-English explanation.

Paste any text below your pattern and matches are highlighted instantly. Multiple matches use different colours for easy scanning.

Switch to List view to see every match with its index position, length, and captured group values.

Prebuilt patterns for email, URL, phone numbers (US + Bangladesh), IPv4, dates, hex colors, usernames, passwords, SQL injection, XSS, Markdown parsing, and more.

Export your pattern as ready-to-use JavaScript, Python 3, PHP, or Go code with one click.

Pattern, flags, and test text are all URL-encoded. Share exactly what you're testing.

Global

Find all matches, not just the first one

Ignore case

Makes the match case-insensitive — a matches A

Multiline

^ and $ match start/end of each line, not just the string

Dotall

. matches any character including newlines

Unicode

Enables full Unicode support and Unicode escape sequences

Sticky

Match only from the position indicated by lastIndex

Paste minified or malformed JSON and get it beautifully indented with correct whitespace.

Instant syntax error detection with precise line/column error reporting.

Remove all whitespace for production payloads or API requests.

Auto-generate typed TypeScript interfaces from any JSON object.

Generate Zod validation schemas directly from JSON structure.

Compare two JSON documents and highlight the differences.

Convert JSON arrays to CSV or transform to YAML format.

Syntax-highlighted output with colour-coded keys, strings, numbers, booleans, and nulls

Instant error reporting with stats: key count, nesting depth, arrays, strings, numbers

Auto-generate typed interfaces from any JSON structure with nested types

Generate z.object() schemas with inferred type export ready for your project

Convert JSON arrays to CSV with proper escaping and one-click download

Recursively sort all object keys A→Z for clean diffs and version control

SHA-1, SHA-256, SHA-384, SHA-512. All four generated simultaneously from your input. Copy any individually.

Standard Base64 and URL-safe Base64 (replaces + → - and / → _ for use in URLs and JWTs).

encodeURIComponent / decodeURIComponent — essential for building query strings and parsing URLs.

Convert text to its hexadecimal byte representation and back.

Cryptographically random UUIDs using crypto.getRandomValues(). Generate 1, 5, 10, or 20 at once.

21-character URL-safe unique IDs — shorter than UUID, same entropy. Popular in modern apps.

Protocol (amber), hostname (green), port (blue), path (teal), query string (purple), fragment (grey) — visually distinct at a glance.

Each key=value pair shown separately with individual copy buttons. Useful for debugging API calls with many parameters.

Compose a URL visually: pick protocol, enter host, path, fragment, and add/remove query params dynamically. Output updates live.

Paste a bare hostname like google.com and URLInspector automatically prepends https:// so parsing always works.

Original and modified side-by-side with line numbers. Deletions on the left in red, insertions on the right in green.

Classic unified diff format with + and − prefixes. Mirrors what you see in git diff or GitHub PR reviews.

Live counts of lines added, removed, and unchanged shown in the header as you type.

Export the diff in standard unified patch format — paste directly into a .patch file or GitHub comment.

JSON config, code function refactor, and SQL query — load instantly to see the diff engine in action.

Steps 50–950 generated from your brand color using HSL interpolation, matching Tailwind's methodology. Click any swatch to copy its hex.

Not plain grey — a subtly hue-shifted neutral scale that feels designed and cohesive with your brand color.

Every scale step tested against white and black with AA and AAA pass/fail badges. Know exactly which steps are safe for text.

Live UI mockup using your generated scale. See how your colors look in both modes before committing.

Save up to 100 named palettes and reload them instantly across devices.

CSS Variables, Tailwind Config, SCSS variables, JSON Design Tokens, and Dark Mode CSS — ready to paste into your project.

Fill in your details in Edit mode, then switch to Preview to see the finished invoice exactly as it will print.

Uses the browser's native print dialog targeting only the invoice element. No jsPDF or server needed — clean A4 output.

USD, BDT, EUR, GBP, CAD, AUD, SGD, INR — with correct currency symbols automatically applied throughout.

Subtotal, discount (%), tax (%), and total calculated live as you type. Add or remove line items dynamically.

Your chosen color is applied to the invoice header, table headers, and total bar — instant brand identity.

Save up to 100 invoice templates. Reload a previous client's invoice, update the date and items, and export in seconds.

Export the full invoice data as JSON for your own records or to import into accounting software.

Sortable columns (click any header), filterable rows, colour-coded numeric values in teal. Click any cell to copy its value.

Per-column analysis: row count, empty count, unique values, and for numeric columns: min, max, average, and sum.

Upload a file and CSVStudio automatically detects whether it uses commas, tabs, semicolons, or pipes.

JSON Array (typed — numbers stay numbers, nulls are null), SQL INSERT with your table name, and Markdown table.

Upload .csv, .tsv, or .txt files directly. The filename becomes the default SQL table name.

Save CSV datasets for quick reload — useful for reference data you use across multiple projects.

GET, POST, PUT, PATCH, DELETE, HEAD, OPTIONS — each colour-coded so you always know which method is active.

Bearer token, Basic auth (username + password), and API Key (custom header name). Auth is injected into the request headers automatically.

JSON editor with monospace green text, HTML form (key-value pairs), and raw text. Content-Type header is set automatically.

JSON responses are colour-coded: keys in blue, strings in green, numbers in teal, booleans in amber, nulls in red.

Response time in ms and body size shown in the header bar. Green under 200ms, amber under 1s, red above.

Save up to 100 API requests — URL, method, headers, auth, and body — and reload them instantly.

Header and payload are decoded and pretty-printed the moment you paste a token — no button needed.

exp, iat, and nbf claims are parsed into human-readable dates with a live relative-time countdown and a clear valid/expired badge.

Flags tokens using alg: none — a known JWT vulnerability where the signature is stripped entirely.

Enter the signing secret to verify HS256/HS384/HS512 signatures locally via the Web Crypto API. RS/ES/PS algorithms need a public key and aren't supported.

Unix seconds and milliseconds update every second, so you always have a reference point.

Paste a 10-digit or 13-digit timestamp and it's interpreted correctly without needing to specify the unit.

19 common timezones covering major regions — auto-detects your browser's timezone on load.

Unix seconds/ms, ISO 8601, RFC 2822, localized timezone string, relative time, and day of week — each with a one-click copy.

One swap button flips direction and carries your current output into the new input side.

Handles nested mappings and sequences, including sequences of mappings (e.g. a list of service definitions).

Supports inline arrays [a, b, c] and inline objects {'{a: 1, b: 2}'} alongside standard block-style YAML.

Save frequently converted config snippets and reload them across devices.

Uses crypto.getRandomValues() — the same secure random source browsers use for encryption keys, not Math.random().

Toggle uppercase, lowercase, digits, and symbols independently. Optionally exclude visually ambiguous characters (0/O, 1/l/I).

Generate word-based passphrases (e.g. crown-falcon-marble-42) from a built-in word list — easier to type and remember, still high entropy.

Every generated password shows its entropy in bits and a Weak/Fair/Good/Strong rating based on that value.

Generate 5, 10, or 20 at once with copy-all support.

Breaks queries onto new lines at major clauses (SELECT, FROM, WHERE, JOIN, GROUP BY, ORDER BY, etc.) with consistent indentation.

Collapses a formatted query back to a single line — useful for logging or embedding in application code.

All recognized SQL keywords are automatically uppercased for consistency, regardless of how you typed them.

Save frequently used queries and reload them across devices.

Every key is categorized as Same, Different, Only in A, or Only in B — click any stat card to filter the list.

Values are partially masked (e.g. ab••••••••yz) until you explicitly click Reveal — protects secrets from shoulder-surfing.

One click produces a template with every key from both files and empty values — safe to commit to version control.

🇧🇩 Bangladesh — AamarPay

bKash, Nagad, Rocket, Visa, Mastercard, and 30+ local bank cards. Prices in BDT.

🌍 International — Lemon Squeezy

Visa, Mastercard, PayPal, Apple Pay, Google Pay. 30+ currencies. Powered by Stripe.