Free Developer Tools Online
Format JSON, test regex, encode Base64 and URLs, and generate passwords, UUIDs and hashes free online — in your browser.
Base64 Encoder & Decoder
Encode and decode Base64 free online
Open toolHash Generator
Generate MD5, SHA-1, SHA-256 and SHA-512 hashes online free
Open toolHTML / CSS / JS Minifier
Minify HTML, CSS and JavaScript free online with Terser
Open toolJSON Formatter & Validator
Format, minify and validate JSON free online
Open toolPassword Generator
Generate strong random passwords free online
Open toolQR Code Generator
Generate custom QR codes free in your browser
Open toolQR Scanner & Barcode Reader
Scan QR codes and barcodes with your mobile camera or an image. Read and copy results privately on your device.
Open toolBarcode Label Maker
Create Code 128, EAN, UPC and other barcode labels. Download SVG or PNG and print batch label sheets.
Open toolRegex Tester
Test regular expressions free online
Open toolURL Encoder & Decoder
Encode and decode URLs free online
Open toolUUID Generator
Generate free UUID v4 (GUID) identifiers online in bulk
Open tool Needs API keyAI Regex Generator
Describe the pattern, get a working regular expression
Open tool Needs API keyAI Code Explainer
Plain-English explanations of any code snippet
Open tool DevKitHTML Entity Encoder
Encode HTML special characters safely.
Open tool DevKitHTML Entity Decoder
Decode HTML character references into plain text.
Open tool DevKitText to Unicode Escapes
Convert text to JavaScript Unicode escapes.
Open tool DevKitUnicode Escape Decoder
Decode Unicode escape sequences into characters.
Open tool DevKitJSON to CSV
Convert a JSON array of flat records into a correctly quoted CSV.
Open tool DevKitCSV to JSON
Parse quoted CSV rows into JSON records.
Open tool DevKitJSON Key Sorter
Sort object keys recursively without changing array order.
Open tool DevKitJSON Pretty Printer
Indent valid JSON for easier reading.
Open tool DevKitJSON String Escaper
Create a safe JSON string literal from arbitrary text.
Open tool DevKitXML Formatter
Validate and indent an XML document locally.
Open tool DevKitHTML Text Extractor
Extract readable plain text from pasted HTML.
Open tool DevKitUnix Timestamp to Date
Convert a Unix timestamp to UTC ISO date/time.
Open tool DevKitISO Date to Unix Timestamp
Convert an ISO date/time to seconds and milliseconds since the epoch.
Open tool Needs API keyDevKitAI User Story Generator
Create a reviewed draft using your chosen AI provider.
Open tool Needs API keyDevKitAI Acceptance Criteria Writer
Create a reviewed draft using your chosen AI provider.
Open tool Needs API keyDevKitAI Test Case Generator
Create a reviewed draft using your chosen AI provider.
Open tool Needs API keyDevKitAI Commit Message Writer
Create a reviewed draft using your chosen AI provider.
Open tool Needs API keyDevKitAI README Generator
Create a reviewed draft using your chosen AI provider.
Open tool Needs API keyDevKitAI SQL Query Explainer
Create a reviewed draft using your chosen AI provider.
Open tool Needs API keyDevKitAI Code Review Assistant
Create a reviewed draft using your chosen AI provider.
Open tool Needs API keyDevKitAI CSS Explainer
Create a reviewed draft using your chosen AI provider.
Open tool Coming SoonDevKitJWT Decoder & Inspector
Decode header/payload locally without treating it as verified
Planned toolComing SoonDevKitJSON to TypeScript Types
Generate TypeScript interfaces from example JSON
Planned toolComing SoonDevKitJSON Schema Generator
Generate JSON Schema from representative objects
Planned toolComing SoonDevKitJSON Schema Validator
Validate JSON files against provided schema
Planned toolComing SoonDevKitHTML Beautifier
Reformat pasted HTML consistently
Planned toolComing SoonDevKitCSS Beautifier
Pretty-print or re-indent CSS
Planned toolComing SoonDevKitJavaScript Beautifier
Reformat JavaScript for review without executing it
Planned toolComing SoonDevKitSQL Formatter
Format SQL queries and highlight statements
Planned toolComing SoonDevKitSQL to JSON Data Mapper
Transform exported SQL rows into JSON safely
Planned toolComing SoonDevKitCron Expression Builder
Generate cron schedules and show next run times
Planned toolComing SoonDevKitCron Expression Explainer
Translate cron notation into plain language
Planned toolComing SoonDevKitURL Parser
Inspect query parameters, hostname, port and fragments
Planned toolComing SoonDevKitCSS Clamp Generator
Generate fluid CSS clamp values from screen limits
Planned toolComing SoonDevKitFlexbox Playground
Interactively adjust CSS flexbox layouts
Planned toolComing SoonDevKitCSS Grid Playground
Interactively adjust grid tracks and alignment
Planned toolComing SoonDevKitHTTP Status Code Lookup
Explain status codes with examples
Planned toolComing SoonDevKitHTTP Request Builder
Compose cURL/fetch snippets without sending secrets
Planned toolComing SoonDevKitCSP Header Builder
Create restrictive Content-Security-Policy header rules
Planned toolComing SoonDevKitRegex Replace Preview
Apply matched replacements with safe previews
Planned tool34 available tools. Read each tool’s inputs and processing details before starting.
Frequently asked questions
Are these developer tools really free?
Yes — every tool on this page is completely free.
Is the password generator cryptographically secure?
Yes — it uses your browser’s crypto.getRandomValues(), the same secure random source behind the Web Crypto API.
Which regex flavor does the tester use?
JavaScript (ECMAScript) regular expressions — the same engine your browser and Node.js use.
Is my code or data uploaded?
No. Everything is processed locally in your browser; nothing leaves your device.
Do the tools work offline?
Once the page has loaded, the pure-JavaScript tools keep working without a network connection.