Small tools for the 30 seconds you need one

Generate random v4 and time-ordered v7 UUIDs in your browser, one at a time or up to 1000 at once, and inspect any UUID you paste in.

Percent-encode and decode URLs and query strings, with encodeURIComponent, encodeURI, strict RFC 3986 and form encoding, plus a breakdown of the query parameters.

Encode text or a file to Base64 and decode it back, with correct UTF-8, standard and URL-safe alphabets, optional padding, MIME line wrapping and data: URIs.

Convert YAML to JSON and JSON back to YAML in your browser, following YAML 1.2, with anchors and merge keys resolved, multi-document streams, and syntax errors reported by line and column.

Convert a Unix timestamp to a date and back, with the unit detected from the number, any IANA time zone, ISO 8601, RFC 2822, relative time and ISO week, plus the current epoch ticking live.

Convert identifiers and text to camelCase, PascalCase, snake_case, SCREAMING_SNAKE_CASE, kebab-case, Train-Case, dot.case, path/case and four more at once, one line at a time, with acronyms and digits split the way style guides expect.

Convert CSV to JSON and JSON back to CSV in your browser, following RFC 4180, with the delimiter detected, quoted fields and line breaks handled, optional type inference, and errors reported by line and column.

Render Markdown to HTML in your browser, with a live preview beside the generated source. CommonMark or GitHub Flavored Markdown, raw HTML escaped rather than rendered, and dangerous link schemes dropped.

Format, minify and validate JSON in your browser, with syntax errors explained by line and column, repeated keys listed, and number literals kept exactly as written.

Pretty-print, minify and check XML in your browser, with well-formedness errors reported by line and column, and comments, CDATA sections, processing instructions and mixed content all kept intact.

Format and beautify SQL in your browser across 20 dialects, from PostgreSQL and MySQL to SQL Server, BigQuery and Snowflake, with your own indent width and keyword case, plus a minifier that puts a query back on one line.

Pretty-print and minify GraphQL in your browser, from queries, mutations and fragments to schema definition language, parsed by the reference implementation with syntax errors reported by line and column.

Build a CSS Grid layout visually: set the columns, rows, track sizes and gaps, drag items across cells to place them, and copy the generated CSS and the matching HTML.

Build linear, radial and conic CSS gradients visually: any angle, shape, size and centre, colour stops with their own position and opacity, repeating variants and an interpolation colour space, with the background declaration ready to copy.

Build a flex container by eye and copy the code: direction, wrapping, justify-content, align-items, align-content and gap, plus flex-grow, flex-shrink, flex-basis, align-self and order on any item, with only the properties you changed in the output.

Build a CSS box-shadow visually, with as many layers as you need: offsets, blur, spread, colour with opacity and inset, over a preview whose box colour, background and border radius you set yourself.

Build a CSS border-radius visually: one radius per corner or the elliptical slash syntax for organic blob shapes, with presets, a live preview, the shortest correct shorthand and the corner longhands.

Work out a fluid clamp() declaration from a size at two viewport widths, with the slope and intercept shown, a live preview at any width, a type scale in custom properties and a check that the text still resizes.

Draw a CSS easing curve by dragging its two control points, compare it against linear in a live preview, start from the keyword and named presets, and copy the cubic-bezier() value or a ready transition line.

Check a foreground and background pair against the WCAG 2 contrast thresholds, composite transparency the way a browser does, find the nearest passing colour, and build a tint, shade and harmony palette with the contrast of every swatch.

Every status code in the IANA registry, with its official reason phrase, a plain explanation, the defining RFC and a link straight to the code, plus the vendor codes from nginx and Cloudflare that are not in the registry.

Compare two texts or two JSON documents in your browser: a line diff with word and character highlighting inside changed lines, unified and side-by-side views, options to ignore whitespace, case and blank lines, and a copyable unified patch.