100% Client-Side, Private Developer Tools

DevScratchpad is a suite of 28 privacy-first developer utilities. Every tool runs entirely within your browser using client-side processing. Zero server transmission. Your data, payloads, and tokens never leave your machine.

Smart Clipboard Detection

Copy a raw JWT, cURL command, JSON, SQL, GraphQL operation, PEM certificate, or SSH key and press Ctrl + V (or ⌘V) anywhere outside a form field. DevScratchpad identifies the format and switches tools for you automatically.

Code Formatting

JSON Formatter & Validator

Format, validate, and minify JSON with interactive syntax highlighting.

JSON Schema Validator

Validate JSON data against draft-07 schemas with real-time error reporting.

XML Formatter

Pretty print and format XML documents.

SQL Formatter

Format SQL queries (PostgreSQL, MySQL, SQLite, standard SQL) with proper indentation.

GraphQL Formatter

Format GraphQL queries, mutations, and schema definitions.

Security & Identifiers

UUID / ULID / NanoID Generator

Generate UUID v4, UUID v7, ULID, and NanoID strings in bulk, locally in your browser.

JWT Decoder & Inspector

Decode JSON Web Tokens locally. Inspect header and claims, and verify HS256 signatures with your secret.

Hash Generator (MD5, SHA256, SHA512)

Computes MD5, SHA-1, SHA-256, and SHA-512 in parallel client-side in your browser.

HMAC Generator

Compute Hash-based Message Authentication Codes (HMAC) using SHA256, SHA512, etc.

Base64 / Hex / Binary Multi-Inspector & Image Previewer

Auto-detects Base64, URL-safe Base64, Hex, Binary, URL-encoded, and Data URL input and converts it to every format, plus a Canonical Hex Dump.

X.509 Certificate & CSR Decoder

Decode X.509 PEM certificates and PKCS#10 CSRs in your browser. Inspect Subject and Issuer CN, validity dates, public key info, and fingerprints.

SSH Keypair Generator & Randomart Visualizer

Generate cryptographically secure Ed25519, RSA (2048/4096), and ECDSA P-256 SSH key pairs directly in your browser with OpenSSH Randomart.

Bcrypt / Argon2 / PBKDF2 Password Hash Verifier & Generator

Generate Bcrypt, Argon2id, PBKDF2, and SCrypt hashes (with Bcrypt cost and PBKDF2 iteration controls) and verify passwords against Bcrypt hashes.

Mock Data Generator

Generate thousands of rows of realistic dummy data (JSON, CSV, SQL) using Faker.js.

Networking & Time

Cron Expression Visualizer

Translates complex cron schedules into plain English with a 5-column breakdown grid.

CIDR Calculator & Subnet Inspector

Calculate IPv4 subnet masks, broadcast addresses, and usable ranges.

Epoch / Timestamp Converter

Convert Unix epoch timestamps to human-readable dates (Local and UTC).

Code Converters

JSON to TypeScript Interfaces

Instantly infer TypeScript interfaces from a JSON payload.

JSON to Zod Schema

Infer Zod validation schemas directly from JSON payloads.

JSON to Go Struct

Convert JSON payloads into Go struct definitions with json tags.

SVG to JSX Converter

Convert raw SVG markup into a React JSX component.

cURL to Python Requests

Translate bash cURL commands into Python `requests` code.

cURL to JavaScript Fetch

Translate bash cURL commands into JavaScript fetch() API calls.

cURL to Go HTTP Request

Translate bash cURL commands into Go `net/http` client code.

YAML to JSON / JSON to YAML Converter

Bidirectional YAML and JSON conversion with syntax validation.

Diff & Text Optimization

Diff Checker & Text Compare

Monaco side-by-side or inline code diffing with character-level additions and deletions.

CSS / SVG Minifier

Minify and compress CSS stylesheets and SVG graphics.

Regex Tester & Matcher

Real-time RegExp testing with flags (g, i, m, s, u, y), match lists, and substitution preview.

Why DevScratchpad?

Magic Paste Auto-Detection: Never waste time searching through sidebars. Just press Ctrl + V and DevScratchpad auto-detects JWTs, cURL, JSON, SQL, GraphQL, certificates, SSH keys, and simple cron expressions instantly.
Zero Server Transmission: Everything happens 100% in your browser. We don't have any backend databases or tracking servers that log your confidential tokens.
Lightning Fast: Zero API latency. Formatting, conversion, and decoding execute instantly in local browser memory.
Installable App: Install DevScratchpad as an app in supported browsers (Chrome, Edge). It needs a connection to load.
Free & Open: Accessible to all engineers worldwide without ads, sign-ups, or usage limits.

Frequently Asked Questions

How does Magic Paste (Ctrl + V) work?

When you press Ctrl+V (or ⌘V) outside a form field, the DevScratchpad client-side parser inspects your clipboard. If it detects a recognizable format (like a JWT token, cURL snippet, valid JSON, SQL query, GraphQL operation, or PEM certificate), it switches you directly to the relevant tool and pre-populates your formatted output with zero friction.

What tools does DevScratchpad offer?

DevScratchpad provides 28 browser-based developer tools including SVG to JSX, JSON/XML/SQL formatters, JWT decoders, Hash/HMAC generators, Base64/URL encoders, timestamp converters, CIDR calculators, diff checkers, and more.

Is DevScratchpad really free?

Yes, DevScratchpad is 100% free to use with no hidden fees, premium tiers, or account registration required.

Does DevScratchpad work offline?

Partly. All tools run on client-side JavaScript with no API calls, so a tool that is already open keeps working if your connection drops. Pages are not cached for offline use, so loading a new tool needs a connection.

Is my data safe with DevScratchpad?

Absolutely. Your data never leaves your device. All inputs, text, tokens, and payloads are processed locally in your browser's memory and are never transmitted to any remote servers or databases.

100% Client-Side Privacy Guarantee

All inputs are processed entirely inside your browser's memory using JavaScript. No data is ever transmitted to any server. Your tokens, JSON payloads, cURL commands, and timestamps never leave your machine.