Your files stay on your device
File processing runs in your browser. Documents are not uploaded to our servers. The site may download processing engines and send usage or feedback events without file contents.
How we handle your dataLaboratorU
Structure checks
Inspect HTML, XML, Markdown, CSV, diff, and regex structure locally before publishing or sharing.
JSON DiffCompare two JSON documents by parsed path locally, ignoring whitespace and key order.JSON SchemaValidate JSON against a small local JSON Schema subset for quick contract checks.HTML StructureCheck pasted HTML for headings, links, images, forms, and basic document structure locally.XMLFormat and validate XML locally in your browser.Markdown OutlineExtract heading structure, links, images, and list counts from Markdown locally.CSV StructureCheck CSV rows, columns, headers, and inconsistent row lengths locally.Remove Duplicate Rows from CSVRemove rows that repeat the same values in the columns you choose. Keep the first or last copy and download the removed rows too.Validate CSV FieldsCheck required values, whole numbers, numbers, ranges and allowed values column by column. Every problem is listed with its row and column; the file is not changed.Compare Two CSV FilesMatch rows of two CSV files by a unique key and list added, removed and changed rows with old and new values.Merge CSV FilesAppend the rows of two CSV files into one file. Columns are matched by name, not position; files with different columns need your explicit choice.Split CSV FileSplit a large CSV file into smaller files with a set number of rows. Every file keeps the header row; cells with line breaks stay whole.robots.txtInspect pasted robots.txt directives and common crawl-blocking signals locally.robots.txt GenGenerate a static robots.txt draft from local rules for small sites and utility domains.Sitemap URLsExtract URLs, lastmod values, and sitemap index references from pasted sitemap XML locally.Sitemap XMLGenerate a static sitemap.xml file from a site URL and local path list.hreflangGenerate alternate-language link tags from local URL fields for multilingual sites.ICS InspectInspect pasted ICS calendar text for event fields and basic structural warnings.vCard InspectInspect pasted vCard text for contact fields and basic structural warnings.Text DiffCompare two text blocks line by line locally in your browser.RegexTest JavaScript regular expressions against sample text locally.Meta/OG PreviewGenerate or inspect page meta, Open Graph, and social preview tags locally.OG ImageGenerate a 1200x630 SVG social preview image locally from pasted fields.Reading GuideGenerate a local table of contents, reading time, and progress bar snippet.Back to TopGenerate a lightweight scroll-to-top button snippet locally.