Developer tools that run in your browser

Browse by category

• SVG2 tools
• JSON8 tools
• HTML2 tools
• Markdown2 tools
• XML5 tools

Available tools

• EncodingBase64 Decode and EncodeDecode Base64 to text or a file, encode text or images to Base64 and data URIs. URL-safe base64url supported. Runs in your browser, nothing is uploaded.
• CSVConvert CSV to JSON OnlineConvert CSV or TSV to JSON (array of objects, nested keys, JSON Lines) with type detection and delimiter auto-detect. Big files in your browser, no upload.
• CSVConvert CSV to XML OnlineConvert CSV to XML with custom root and row element names, attributes or child elements per column. Private, in your browser.
• HTMLOnline HTML Editor with Live PreviewEdit HTML, CSS and JavaScript in your browser and see changes live. Free online HTML editor with autocomplete, formatting and download. Nothing is uploaded.
• HTMLHTML Viewer OnlinePaste or open an HTML file and see it rendered instantly. Free online HTML viewer with live preview and responsive modes. Files never leave your browser.
• JSONJSON Editor OnlineEdit JSON in tree, code or table mode with instant validation, formatting, search and undo. Free online JSON editor – nothing is uploaded.
• JSONMinify & Compress JSON OnlineMinify JSON by removing whitespace and line breaks, see size savings, optionally gzip the result. Large files, in your browser, no upload.
• JSONConvert JSON to CSV OnlineConvert JSON arrays and nested objects to CSV with automatic flattening, column selection and custom delimiter. Large files in your browser, nothing uploaded.
• JSONConvert JSON to Excel (XLSX)Turn JSON into an Excel spreadsheet with proper columns, nested data flattening and multiple sheets. Works in your browser, no upload, no sign-up.
• JSONConvert JSON to HTML TableTurn JSON arrays into a clean HTML table (or nested lists) with optional CSS classes, then copy the markup or preview it. In your browser, no upload.
• JSONConvert JSON to XML OnlineConvert JSON to well-formed XML with custom root element, attribute mapping and pretty-print. Runs in your browser, nothing uploaded.
• JSONConvert JSON to YAML OnlineConvert JSON to clean YAML with configurable indentation, quoting and key order. Great for Kubernetes, Docker Compose and OpenAPI. Runs in your browser.
• JSONJSON Viewer & Formatter OnlineView, format and validate JSON in a collapsible tree or code view. Free online JSON viewer for large and .gz files – nothing is uploaded.
• MarkdownMarkdown Editor OnlineWrite Markdown with a live preview, formatting toolbar and autosaved draft. Export to .md, HTML or PDF. Free online Markdown editor – nothing is uploaded.
• MarkdownMarkdown Viewer OnlineOpen a .md file or paste Markdown and see it rendered GitHub-style with tables, code highlighting, math and diagrams. Free, private, in your browser.
• SVGConvert SVG to PNG OnlineConvert SVG to PNG at any size (1x–8x or custom width) with a transparent or solid background. Batch convert many files in your browser – no upload.
• SVGSVG Viewer OnlineOpen SVG files or paste SVG code and preview them with zoom, background options and code view. Convert to PNG in one click. Free, private, in your browser.
• EncodingURL Decoder and EncoderDecode and encode URLs and percent-encoded text, like encodeURIComponent and encodeURI. See URL parts and query parameters in a table. In your browser.
• EncodingUUID GeneratorGenerate random UUID v4 or time-ordered UUID v7, one or up to 10,000 at once, in upper or lower case, with or without hyphens. Validate and inspect UUIDs.
• XMLOnline XML EditorEdit XML with syntax highlighting, auto-closing tags, pretty-print and well-formedness check. Open and save .xml files locally, nothing uploaded.
• XMLConvert XML to CSV OnlineConvert XML to CSV by choosing which element becomes a row; nested elements and attributes become columns. Preview the table, then download. In your browser.
• XMLConvert XML to Excel (XLSX)Convert XML files to Excel spreadsheets: choose the repeating element, get clean columns from nested tags and attributes. No upload, works in your browser.
• XMLConvert XML to JSON OnlineConvert XML to clean JSON with control over attributes, text nodes, arrays and namespaces. Works offline in your browser, no file upload.
• XMLXML Viewer OnlineOpen XML files in a collapsible tree or formatted code view, search with XPath, validate structure. Handles large and .xml.gz files, nothing uploaded.
• YAMLConvert YAML to JSON OnlineConvert YAML to JSON instantly with syntax validation and clear error messages. Multi-document YAML, anchors and merge keys supported. Private, in your browser.

No tools match your search.

Coming soon

• HTML Minifier
• HTML to Markdown
• HTML to Text
• Markdown to PDF
• Markdown to HTML
• Markdown to Word
• SVG Optimizer
• SVG Editor
• PNG to ICO
• Text to HTML
• CSV Viewer
• YAML Viewer

Why these tools

• Private by design: files are processed locally with JavaScript and WebAssembly.
• Fast: no upload, no queue, no sign-up.
• Safe previews: untrusted HTML runs in an isolated sandbox.