53 tools and growing

Developer tool library

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53 tools shown

Suggested starting points

Format a payload JSON Formatter → Convert an API request cURL Converter → Work with an ESP32 board ESP32 Flasher →

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Format & Compare

Format JSON, SQL, YAML and XML, or compare structured and plain text.

Explore format & compare →

JSON Formatter & Validator

Format, validate, and minify JSON instantly with a browser-first editor.

Sort keysCopy compact

SQL Formatter

Format raw SQL with dialect support for SQL Server, MySQL, PostgreSQL, SQLite, and more.

6 dialectsSize stats

YAML Formatter & Validator

Format and validate YAML, or convert between YAML and JSON. Essential for Kubernetes, Docker, and CI configs.

Format YAMLYAML ↔ JSON

JSON Diff — Compare Two JSON Documents

Compare two JSON documents semantically: key order ignored, big numbers exact, arrays by position or by key, ignore paths, and export an RFC 6902 JSON Patch.

Key order ignoredExact big numbers

Text Diff — Compare Two Texts Side by Side

Compare two texts by line, word or character with side-by-side and unified views, whitespace/case/line-ending options, Unicode normalization and .patch export.

Line / word / charCRLF & Unicode checks

XML Formatter, Validator & XPath Tester

Pretty-print or minify XML while preserving comments, CDATA, entities and xml:space; validate with line and column; test XPath; convert XML to JSON.

Keeps comments & CDATAErrors with line/column

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Code & API Conversion

Convert between C#, JSON, SQL, XML and API request formats.

Explore code & api conversion →

C# Class to JSON Converter

Generate sample JSON from C# classes, including nested classes, dictionaries, and lists.

Nested classesDictionary support

JSON to C# Class Converter

Convert JSON payloads into C# classes with nested types, arrays, DateTime, and Guid detection.

Custom root nameDateTime detection

C# Class to SQL Table Generator

Generate CREATE TABLE statements from C# classes for SQL Server, MySQL, and PostgreSQL.

T-SQL, MySQL, PostgreSQLPK from Id or [Key]

JSON to SQL Table Generator

Generate CREATE TABLE scaffolding from JSON objects with nested structures and arrays.

Nested object supportQuick schema drafts

Mock API Generator

Generate realistic fake JSON data from a JSON Schema, OpenAPI 3.x spec, or a sample JSON object shape.

JSON SchemaOpenAPI 3.x

SQL CREATE TABLE to C# Entity Class (EF Core)

Turn CREATE TABLE statements from SQL Server, PostgreSQL, MySQL or SQLite into EF Core entity classes — data annotations, Fluent API, or plain POCOs.

4 SQL dialectsEF Core attributes or Fluent API

cURL to C# HttpClient Converter (and fetch, Python, Go, PHP)

Paste a curl command — including Chrome's "Copy as cURL" for bash or Windows cmd — and get C# HttpClient code, or JavaScript fetch, axios, Python requests, PHP or Go.

C# HttpClient firstbash, cmd & PowerShell input

XML to C# Class Generator (XmlSerializer)

Generate C# classes with XmlSerializer attributes from an XML sample — attributes, repeated elements, namespaces, CDATA and type inference.

XmlSerializer attributesNamespaces

C# to TypeScript Converter

Convert C# classes, records and enums into TypeScript interfaces or types that match what System.Text.Json actually sends.

Matches System.Text.JsonRecords & generics

CSV to JSON & JSON to CSV Converter

Convert CSV to JSON and back. Auto-detects comma, semicolon, tab and pipe; keeps leading zeros; handles quotes, BOMs, ragged rows and duplicate headers; Excel-safe export.

Keeps leading zerosAuto-detect delimiter

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Test & Debug

Check patterns, schedules, queries, accessibility and .NET formatting.

Explore test & debug →

Regex Tester & Builder

Live regex testing with match highlighting, capture groups and flag controls, plus a .NET compatibility checker.

Live matchingGroup capture

Cron Expression Parser

Parse standard, Quartz.NET and Hangfire cron expressions into plain English and see the next 12 scheduled run times.

Quartz.NET & HangfireNext 12 runs

GraphQL Playground

Write and execute GraphQL queries against a schema with mock data — no server needed.

Mock resolversSchema explorer

SQL Runner (SQLite)

Run SQL queries against an in-browser SQLite database. Paste your schema, seed data, and query — instant results.

SQLite WASMSchema explorer

Accessibility Checker

Audit HTML for WCAG 2.1 AA accessibility violations using axe-core — critical, serious, moderate, and minor issues.

axe-coreWCAG 2.1 AA

.NET Format String Tester (C# ToString)

Test C# DateTime, DateTimeOffset and number format strings — standard and custom — in five cultures, with output verified against real .NET 8 and a table of common formats.

Matches real .NET 8Standard & custom formats

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Web & Design

Minify web assets and build accessible colors and CSS effects.

Explore web & design →

CSS Minifier & Beautifier

Minify or beautify CSS for quick inspection and front-end debugging.

MinifyBeautify

JavaScript Minifier

Reduce JavaScript payload size for quick inspection and manual optimization.

Smaller bundlesQuick checks

HTML Minifier

Collapse HTML markup, remove comments, and preview smaller output instantly.

Preserve comments optionWhitespace collapse

Color Palette Generator

Extract color palettes from images or build them manually. Export to CSS variables, Tailwind config, SCSS, or JSON with WCAG contrast grades.

Extract from imageWCAG contrast

Color Converter — HEX, RGB, HSL, OKLCH, Lab

Convert any CSS color between HEX, RGB, HSL, HWB, Lab, LCH, OKLab and OKLCH at once, with gamut warnings and the nearest named color.

10 CSS formatsOKLCH & gamut mapping

WCAG Contrast Checker

Check the WCAG 2 contrast ratio of text and background colors for AA and AAA, and get the nearest passing color with the same hue.

AA & AAASuggests passing colors

Tailwind Color Shade Generator (50–950)

Turn one brand color into a Tailwind 50–950 scale in OKLCH, with contrast against white and black, as Tailwind v4 @theme, v3 config, CSS variables, SCSS or JSON.

OKLCH, in sRGB gamutTailwind v4 & v3

CSS Gradient Generator (Linear, Radial, Conic)

Build linear, radial and conic CSS gradients with draggable stops, OKLCH interpolation (with a fallback line), repeating patterns, and Tailwind arbitrary-value output.

Linear / radial / conicin oklch + fallback

CSS Box Shadow Generator (Layered Shadows)

Design layered CSS box shadows with offset, blur, spread, color and opacity per layer, inset shadows and presets, previewed on light and dark backgrounds.

Up to 8 layersLight & dark preview

Encoding & IDs

Encode payloads and generate UUIDs or QR codes.

Explore encoding & ids →

Base64 Encode / Decode

Convert text to Base64 and back with Unicode-safe browser-side processing.

File drag-and-dropBase64URL mode

URL Encode / Decode

Encode special characters for URLs or decode percent-encoded strings safely.

Component vs Full URLSafe decode errors

UUID Generator & Validator

Generate UUID v1, v4, and v7 in bulk, or validate and inspect any UUID — with .NET Guid.ToString N, D, B, P and X formats.

v1 / v4 / v7Bulk generate

QR Code Generator & Scanner

Generate QR codes from any text or URL, and scan QR codes from images or your webcam.

Generate QRScan image / webcam Camera permission for webcam scanning

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Security & Cryptography

Inspect tokens and certificates, create hashes, signatures and passwords.

Explore security & cryptography →

JWT Decoder

Decode JWT header and payload locally so you can inspect claims and expiry quickly.

HMAC verificationClaims inspector

Hash Generator

Generate MD5, SHA-1, SHA-256, SHA-384, and SHA-512 hashes from text.

File hashingMultiple algorithms

JWT Generator & Signer (HS256, HS384, HS512)

Create and sign JSON Web Tokens with HS256/384/512 for testing APIs — claim helpers for iat, exp, nbf and jti, secret encoding options, and warnings for common mistakes.

HS256 / HS384 / HS512Claim helpers

HMAC Generator & Webhook Signature Verifier

Generate HMAC-SHA1/256/384/512 in hex or Base64, and verify GitHub, Stripe, Slack and Shopify webhook signatures against the raw request body.

SHA-1 to SHA-512GitHub / Stripe / Slack / Shopify

SSL Certificate Decoder (X.509 & CSR)

Decode PEM or DER certificates, chains and CSRs: subject, SANs, expiry, key type, extensions, fingerprints and chain order with signature checks. Private keys are refused.

Certificates, chains & CSRsExpiry & SAN check

Bcrypt Hash Generator & Verifier

Hash a password with bcrypt at cost 4–15, verify a password against a $2a$/$2b$/$2y$ hash, and inspect a hash's version, cost and salt. Runs in a worker; nothing is stored.

Cost 4–15, cancelable$2a$ / $2b$ / $2y$

Password, Passphrase & API Key Generator

Generate strong passwords, EFF-wordlist passphrases and developer secrets (hex, Base64URL, UUID v4, prefixed API keys) with crypto.getRandomValues and exact entropy.

crypto.getRandomValuesEFF passphrases

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Config & DevOps

Convert configuration and calculate networks, permissions and time.

Explore config & devops →

Env Variable Converter

Convert .env files to Dockerfile, docker-compose, GitHub Actions, Vercel, Kubernetes ConfigMap, and more.

8 output formatsSecret masking

appsettings.json ↔ Environment Variables

Flatten ASP.NET Core appsettings.json into Section__Key environment variables for .env, Docker Compose, Kubernetes, Azure App Service, PowerShell, and bash — or rebuild the JSON from env vars.

Double-underscore keys8 output formats

Unix Timestamp Converter

Convert Unix timestamps in seconds, milliseconds, microseconds or nanoseconds, and .NET ticks, to dates in any time zone, and dates back to timestamps — including DST edge cases.

s / ms / µs / ns.NET ticks

CIDR / Subnet Calculator (IPv4 & IPv6)

Network, broadcast, host range and counts for any CIDR block, AWS/Azure/GCP reserved addresses, subnet splitting, range-to-CIDR and overlap checks. IPv4 and IPv6.

IPv4 & IPv6AWS / Azure / GCP reservations

Chmod Calculator (Octal ⇄ rwx)

Convert Unix permissions between checkboxes, octal (755) and symbolic (rwxr-xr-x), including setuid, setgid and sticky bits; parse ls -l output; get the chmod command.

Octal ⇄ symbolic ⇄ checkboxessetuid / setgid / sticky

docker run to Docker Compose Converter

Convert one or more docker run commands into a Compose file (compose.yaml, no obsolete version key): ports, volumes, env, networks, healthchecks, GPUs and more.

Compose SpecificationMultiple services

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Embedded & Hardware

Work with bytes, firmware and serial devices for Arduino and ESP32.

Explore embedded & hardware →