Paste in, debug, move on

    Fewer tabs between you and a working build.

    Format JSON, inspect JWTs, hash strings, turn SVGs into JSX and open SQLite files without installing anything or pasting your data into someone else's server.

    Explore Tools

    JSON Formatter

    Beautify, validate and minify JSON data with syntax highlighting.

    Base64 Encoder/Decoder

    Encode images to Base64 and decode Base64 strings back to images.

    URL Encoder/Decoder

    Encode text to URL-safe format and decode URL-encoded strings.

    Hash Generator

    Generate cryptographic hashes instantly from any text. Supports SHA-256, SHA-512, MD5, PBKDF2, HMAC-SHA-256 and HMAC-SHA-512.

    JWT Encoder/Decoder

    Decode, verify and generate JSON Web Tokens (JWT) instantly.

    Markdown Previewer

    Write or paste Markdown and MDX and see a live rendered preview instantly. Includes word count, reading time, import, export and copy.

    SVG to React JSX

    Convert SVG markup into optimized React JSX components instantly.

    SQLite DB Viewer

    Upload and browse SQLite database files, schema and tables entirely in your browser with full privacy.

    How It Works

    Eight browser-based utilities for the small translation jobs that fill a debugging session: make a payload readable, see inside a token, hash a value or turn a design asset into a component.

    Fewer tabs between a bug report and a fix

    Debugging is mostly small translation jobs. Make this payload readable. See what is inside this token. Turn this icon into a component. These tools do the translating in your browser, so you can paste real payloads and tokens without sending them to somebody else's server.

    Pick by task

    If you need toUse
    Read, validate or shrink a JSON payloadJSON Formatter
    Inspect token claims, verify an HS256 signature or build a test tokenJWT Encoder/Decoder
    Turn an image into a Base64 string or data URL, or back againBase64 Encoder/Decoder
    Percent-encode a query value or read an encoded oneURL Encoder/Decoder
    Hash text with SHA-256, SHA-512 or MD5, or compute PBKDF2 and HMAC valuesHash Generator
    Preview Markdown or MDX while you writeMarkdown Previewer
    Browse the tables and schema of a .db, .sqlite or .sqlite3 fileSQLite DB Viewer
    Turn raw SVG into a React componentSVG to React JSX

    Know the limits before you start

    A few honest notes save time. The JWT tool verifies HS256 signatures only. The Base64 tool works with images rather than arbitrary text. The SQLite viewer is for browsing, sorting, searching and exporting to CSV or JSON, and it does not yet offer a SQL console or open encrypted databases. The Markdown Previewer detects MDX but shows JSX tags as plain text instead of running them.

    A habit worth keeping

    Decoding is not trusting. Anyone can read a JWT payload, and a hash is not encryption. Use these tools to inspect and debug, and keep real verification and secrets on your server.

    Frequently Asked Questions

    Common questions about our free developers tools and calculations.

    No. Formatting, decoding, hashing, converting and opening SQLite files all happen in your browser. Your payloads, tokens and secret keys are never transmitted, which makes these tools safer than sites that process input on their own server.

    JSON is stricter than a JavaScript object. The usual culprits are trailing commas, single quotes instead of double quotes, unquoted keys and missing commas between pairs. The formatter points to the line and character where parsing failed, so you can fix the problem and beautify or minify once it passes.

    Yes, with limits. Decoding shows the header and payload to anyone, with no key needed. Verifying needs the secret and re-computes the signature to prove the token was not altered. The tool supports HS256 for verifying and generating tokens, while asymmetric algorithms such as RS256 are not available yet. A decoded payload is readable, not proof of anything, until the signature is verified.

    It is built around images. You can drop a PNG, JPG, GIF, WebP or SVG file to get a Base64 string or a full data URL, or paste a Base64 string to preview and download the image it holds. For plain-text strings, use your language's built-in Base64 functions. Files under about 10 MB work best, since very large images can slow the browser.

    Encoding replaces characters that are unsafe in a URL, such as spaces and symbols, with percent codes like %20. Letters, numbers, hyphens and underscores are left alone, and non-English text and emoji are handled too. Decoding reverses the process so you can read a query string you received. The result updates as you type.

    Use SHA-256 or SHA-512 for general integrity checks. MD5 is broken for security purposes, so keep it for legacy checksums that still expect it. PBKDF2 adds a salt and iteration count and is meant for deriving keys from passwords, while the HMAC options need a secret key and prove who produced a message. All six results appear at once, as hex or Base64, so you can compare them.

    No. It recognises MDX when it sees import statements or JSX tags and switches its badge, but the components are shown as plain text in the preview because running arbitrary JSX in the browser would be a security risk. You get a live preview of the Markdown itself, plus word count, reading time, and import or export of .md and .mdx files.

    Standard SQLite 3 files with a .db, .sqlite or .sqlite3 extension open up to 1,000 MB, though speed depends on your device's memory. Encrypted databases such as SQLCipher are not supported, and there is no SQL console yet. You can browse the schema, page through tables with sorting and search, inspect cell values and export data as CSV or JSON.

    It converts kebab-case attributes like stroke-linecap to camelCase, swaps class for className, turns inline style strings into React style objects and removes needless XML such as xmlns. You can also output TypeScript, wrap the component in React.memo for icons used many times and clean up IDs that might clash on a page.