Developer Tools — Format, Encode and Generate Data Free
Developer tools format, encode and generate the small artefacts coding produces — JSON, HTML, CSS, JavaScript, SQL, Base64, hashes, UUIDs and timestamps — without sending your code anywhere.
All Developer tools
- Base64 Encoder & Decoder
Encode text to Base64 and decode it back with Unicode fidelity.
- Code to Image Converter
Code to image converter to transform source code into beautiful screenshots with macOS window frames, syntax themes, and gradients.
- Cron Expression Builder
Cron expression builder to construct, parse, and explain schedules with human-readable descriptions in Arabic and English.
- CSS Formatter & Minifier
Indent tangled stylesheets or minify them while keeping licenses intact.
- Diff Checker
Compare two text or code snippets to highlight added, removed, and modified lines in your browser.
- Hash Generator
Compute cryptographic hashes (MD5, SHA-1, SHA-256, SHA-384, SHA-512) in the browser.
- HTML Formatter & Minifier
Indent messy HTML readably or minify it, with scripts kept verbatim.
- JavaScript Formatter & Minifier
Format or minify JavaScript safely: parsed, never executed, in a worker.
- JSON Formatter & Validator
Pretty-print, minify, and validate JSON with line-precise errors.
- JWT Claims Decoder (Read Only)
Read-only JWT decoder to parse and inspect claims offline with zero signature verification and complete in-browser privacy.
- Markdown HTML Converter
Convert Markdown to HTML or HTML back to Markdown locally, with clean GFM output.
- Password Generator
Generate strong random passwords or memorable passphrases locally with Web Crypto.
- Regex Tester
Test JavaScript regex patterns live: matches, groups, and indices.
- SQL Formatter
Format SQL readably with dialect, keyword-case, and indent options.
- Unix Timestamp Converter
Convert Unix timestamps to dates and ISO dates back, with relatives.
- URL Encode/Decode
Percent-encode or decode strings with full Unicode support.
- UUID Generator
Generate cryptographically secure UUIDs (v4 random, v7 timestamp-based).
- Security Headers Builder
Interactive security headers builder to configure CSP, HSTS, X-Frame-Options, and CORS for Nginx, Cloudflare, and Next.js with zero server uploads.
- Regex Visualizer & Explainer
An interactive regex visualizer and explainer to inspect syntax tokens, test patterns in real time, and debug regular expressions locally.
- Dockerfile & Compose Generator
Production-ready Dockerfile and Compose generator with multi-stage builds, non-root users, and security hardening for containers locally.
- Chmod Permissions Calculator
Interactive chmod permissions calculator to convert Linux file access rights between octal numbers, symbolic notation, and bash commands.
- Diagram & Flowchart Maker
Interactive diagram and flowchart maker to build Mermaid architecture graphs and sequence diagrams with high-res SVG export in your browser.
- Smooth Shadow Generator
Interactive smooth shadow generator to build multi-layered realistic CSS and Tailwind box-shadows with real light physics in your browser.
- cURL to Code Converter
Convert cURL commands to idiomatic code in Fetch, Axios, Python, Go, PHP, Rust, and C# with this fast, private, in-browser cURL code converter.
- JSON Diff & JSONPath Finder
Compare two JSON files and extract exact JSONPath locations with our visual json diff path finder. Highlight added, removed, and modified keys.
- IP Subnet Calculator
Calculate IPv4 subnet masks, CIDR notation, network and broadcast addresses, usable host IP ranges, and binary bit breakdowns with our free subnet calculator.
- Markdown Table Generator
Interactive visual spreadsheet editor to build, format, and export clean Markdown tables.
- CSS Glassmorphism Generator
Design modern frosted glass UI components with instant CSS and Tailwind export.
- SVG Pattern Generator
Create seamless repeating SVG patterns and export to CSS background, Data URI, and Tailwind.
- JWT Debugger & Signature Verifier
Decode, inspect, and verify JSON Web Tokens (JWT) in real time with HMAC-SHA256 signature verification and complete browser privacy.
- Advanced CSS Gradient Generator
Design linear, radial, and conic CSS gradients with multi-stop color pickers and instant Tailwind arbitrary exports.
- SVG Favicon & Web Manifest Generator
Design modern, scalable SVG favicons with emoji, letters, and custom shapes, plus instant HTML head and manifest code.
Developers spend odd minutes on repetitive chores: a payload that must become readable, a token that needs decoding, an identifier to mint, a pattern to test. This group bundles those errands into single-purpose pages. Paste tangled JSON, HTML, CSS, JavaScript or SQL and receive indentation a human can follow, or minified output when bytes matter. Encode text to Base64 or turn it back, escape a URL, translate Unix timestamps into readable dates, generate cryptographic hashes and random UUIDs, or experiment with regular expressions and inspect every captured group. Validation is strict and errors name the offending line, so a malformed document is reported instead of silently patched. The tools suit backend engineers, data wranglers and anyone gluing systems together who wants a quick answer without opening an editor. Sensitive payloads stay private because parsing and formatting occur entirely inside the tab; nothing is posted to a remote service and no history survives a refresh.
Formats and limits are described per tool; each tool page states the ones that tool actually accepts and enforces.
Reading, repairing and minting the artefacts code produces
The recurring task here is dealing with something a program spat out: a compacted payload, an encoded token, a timestamp, an identifier. Readability comes first, so pretty-print the JSON and validate it before you hunt for the fault. If the payload is a web document, indent the HTML for a readable diff, then minify it again once the fix is in. Tokens come next: decode the Base64 payload to see what it really carries, and compute a checksum to compare two builds when you need to prove the files match.
The most common mistake is editing minified output by hand and breaking the syntax in the process. A close second is assuming a formatter also executes or validates behaviour; these pages parse structure and never run your code. Developers also paste secrets into a formatter without thinking, then worry afterwards. Treat keys as live material, keep them off shared screens, and remember that a decoded token can reveal more than expected. Comparing a hash before and after a change catches drift that eyeballing never will.
Pick by output rather than habit. Formatting wants a language-specific page, encoding wants the Base64 or URL tools, identity wants the UUID generator, and time wants the timestamp converter. Regular expressions and SQL have their own playgrounds, so test a pattern in isolation before pasting it anywhere real.
Aim to keep the routine dull and repeatable. Capture the failing input before altering it, format a duplicate, and diff both copies so the genuine edit stays tiny. When a service rejects a request, decode the envelope and inspect field names instead of rewriting the entire body. Generate unique identifiers rather than inventing plausible ones, because a collision costs far more than a moment of patience. Escape every value destined for a query string, and never confuse percent-encoding with secrecy; anything reversible should be treated as visible text.
Compare your options
| Tool | Best for | Input | Output |
|---|---|---|---|
| Base64 Encoder & Decoder | Encoding or decoding Base64 text | Plain text or a Base64 string | The converted text with Unicode intact |
| CSS Formatter & Minifier | Making a stylesheet readable or smaller | CSS source | Indented CSS, or minified CSS with licences kept |
| Hash Generator | Producing checksums and digests | Text | MD5, SHA-1, SHA-256, SHA-384 or SHA-512 hex |
When this category is NOT the answer
If the material is a whole dataset rather than a single document, formatting it will not restructure its rows. Reshape tabular files with the data tools when the unit of work is a table rather than a snippet.
Start here: a practical Developer workflow
- Beautify or minify the document first with JSON, HTML, CSS, JavaScript or SQL Formatter.
- Encode or decode the result using Base64 Encoder or URL Encode/Decode before it travels.
- Generate supporting values such as hashes, UUIDs or readable timestamps, then copy them out.
Frequently asked questions about Developer tools
Is my code uploaded anywhere?
No. Parsing, formatting and encoding all happen in your browser; snippets, tokens and secrets never leave the machine.
Will the formatters execute my JavaScript?
Never. JavaScript and SQL are parsed, not run, so the tools cannot execute the code you paste.
Which formats can I beautify?
JSON, HTML, CSS, JavaScript, SQL and XML each have a dedicated formatter-and-minifier page in this catalog.
Can I decode a Base64 string back to text?
Yes. Base64 Encoder handles both directions with Unicode support, and URL Encode/Decode covers percent-encoding.
Categories related to Developer
Developer guides: which tool to pick
- JSON formatter, tree viewer, or CSV: which one do you need?
Decide whether to format and validate JSON, explore it as a tree, or flatten it into spreadsheet rows.
- Read, re-delimit, or convert a CSV: which step comes first?
Choose between browsing a large CSV, changing its delimiter, turning rows into JSON, or building CSV from plain lines.
- Format XML, validate it, or convert it to JSON?
Match your XML job to the right tool: readable indentation, structural validation, or a documented JSON mapping.
- Embed an image as Base64 or keep it a separate file?
Decide when a Base64 data URL helps and when it quietly makes pages, emails, or JSON payloads heavier than needed.
- Hash, encrypt, or obfuscate: which protects what?
Match three very different operations to their real purpose: integrity checks, confidential recovery, and casual hiding.
- JSON, HTML, CSS, JavaScript, or SQL: which formatter?
Pick the formatter by language and know which ones parse safely, which keep licenses, and which never execute code.