Free online data and developer tools

JSON, YAML, CSV, XML, SQL, regex, encoding, formatting, minifying, and dozens of developer utilities.

Ninety-four tools make this the developer bench of the site. The conversion core moves between JSON, CSV, XML, YAML and TOML in both directions, with formatters and validators beside them: JSON Formatter, XML Formatter, SQL Formatter, JSON Schema Generator and Validator, JSON Diff, JSONPath Tester and JSON to TypeScript. Spreadsheets are handled by SheetJS, so Excel to CSV, Excel to JSON, CSV to Excel and CSV Cleaner read real XLSX workbooks rather than a renamed CSV. Encoding and crypto utilities cover Base64, URL encoding, HTML entities, string escaping, Unicode lookup and hashing — Hash Generator computes MD5 with spark-md5 and SHA-1, SHA-256, SHA-384 and SHA-512 through the browser's own WebCrypto implementation, which is the same primitive your TLS stack uses. JWT Decoder splits and decodes a token's header and payload locally so a production token never travels to a stranger's server, and JWT Builder goes the other way. Two file viewers are the standouts. SQLite Viewer loads a .sqlite, .db, .sqlite3 or .db3 file into sql.js, a WebAssembly build of SQLite fetched from the sql.js CDN, lists the tables and schema and lets you run real SELECT queries against your own database in memory. Parquet Viewer reads Arrow-compatible Parquet through apache-arrow and shows the schema plus sortable, type-aware rows. Neither file is uploaded; only the engine is downloaded. The rest of the bench is generators and inspectors: UUID and mock data generators, QR Code Generator built on the qrcode library with selectable error-correction levels and ZIP batch export, Regex Tester and Regex Explainer, Cron Parser and Crontab Builder, cURL Builder and Curl to Fetch, Dockerfile, Nginx, htaccess, PWA manifest, OpenAPI and GitHub README generators, Markdown table and editor tools, CSV to Chart, Pivot Table, Code Screenshot, User Agent Parser and a Git diff viewer. Cookie Viewer and LocalStorage Viewer are honest about their reach: browser security means they can only show the cookies and storage entries belonging to this site, never another origin's. Everything runs in the tab, so pasted credentials, customer exports and internal schemas stay on your machine. Two clusters were added after that core. The first is CAD: alongside the read-only DXF Viewer there is now a five-page DXF set, all of it running on a group-code parser in the tab. DXF Converter goes both directions in one page; DXF to SVG expands block references and rewrites arcs as cubic Béziers with each CAD layer becoming an Inkscape-visible group; DXF to PDF emits real PDF path operators rather than a raster, so the print still measures right at 1:1; SVG to DXF flattens Bézier curves to polylines at a tolerance you set in millimetres and writes true CIRCLE entities where the transform is uniform; and PNG to DXF traces a bitmap into closed polylines, showing you the threshold preview before it commits so you can see that a photograph will produce thousands of unusable blobs and a logo will not. The second is the SQL and contact bridge. CSV to SQL scans every value in a column before proposing INT, DOUBLE, DATE or VARCHAR and quotes the output for the dialect you pick, JSON to SQL takes the union of every key across an array of objects so a missing key becomes NULL instead of a shifted column, and CSV to vCard asks you which column holds the mobile number and which the job title before writing one VCARD block per row.

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