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Test JavaScript-style regular expressions in your browser: enter a pattern, toggle global (g), case-insensitive (i), and multiline (m), paste sample text, and see highlighted matches with start indexes. Invalid patterns show a clear error. No signup; your strings stay on your device.

Pretty-print, minify, and validate JSON payloads.

HTTP client in the browser: collections, environments, {{variable}} interpolation, Bearer/Basic/API key/OAuth2/custom auth, JSON/form/urlencoded/multipart/GraphQL bodies, pre-request scripts, history, and code snippets (fetch, Axios, Python, PHP, Go, cURL, C#, Ruby). Sends through Dynamic Duniya’s API proxy (30s timeout). Workspace in localStorage; optional cloud sync when signed in.

Switch CSV → JSON or JSON → CSV. RFC 4180–style CSV parsing (quoted fields, doubled quotes), delimiter choice for import (comma, semicolon, tab, pipe), optional header row or col1… keys, pretty or minified JSON, stats after convert. JSON → CSV needs a non-empty array of objects; union of keys becomes columns; output CSV uses commas. Upload .csv/.json, load examples, copy, or download output.json / output.csv — all client-side.

Convert JSON to YAML or YAML to JSON in the browser with js-yaml: JSON.parse + YAML dump (2-space indent, 120-char wrap) or yaml.load + pretty JSON (2-space indent). Debounced live conversion as you type, line numbers on both sides, Convert now, copy, and download output.yaml / output.json.

Convert XML to JSON or JSON to XML in the browser with fast-xml-parser: attributes map to configurable-prefixed keys (default @), trimmed text nodes, optional compact output, optional UTF-8 XML declaration on JSON→XML, and a root wrapper for bare arrays or scalars. Convert on demand, character/node estimate, copy, download output.json / output.xml.

Merge: first-page previews in a horizontal strip — drag cards to set merge order. Split: optional “Load page previews” then drag thumbnails (four per row, scrollable) to reorder pages before splitting by ranges or every N pages; ranges use preview slot numbers when previews are loaded. Zip when multiple parts. Client-side pdf.js + pdf-lib — max ~35 MB per file, 150 pages, 12 PDFs for merge.

Create a ZIP from many local files (append picks, DEFLATE or STORE) or open a .zip and download entries / selected subset as a new ZIP. JSZip in the browser — ~35 MB archive cap, no password support.

Stamp text (font size, opacity, rotation, corner/center placement) or a JPEG/PNG image across every page using pdf-lib locally. Encrypted PDFs are not supported. Download a watermarked copy — your file never leaves the browser.

Free online color picker for designers and developers: pick from your screen (EyeDropper in Chromium), sample any pixel from an uploaded image, edit in HSV or RGB with alpha, copy hex, RGBA, HSL, ARGB, eight-digit hex, and approximate CMYK — plus saved swatches, tint/shade strips, contrast preview, and a detachable window. Everything runs in your browser; nothing is sent to our servers.

Convert JPEG, PNG, WebP, or GIF sources to JPEG, PNG, or WebP in your browser: live preview updates as you switch format, quality slider for lossy JPEG and WebP, lossless PNG (no quality control). Decoding and encoding stay on your device—no upload. GIF sources decode to a static frame; animation is not preserved in the output file.

Resize or reframe JPEG, PNG, WebP, or GIF entirely in your browser: set target width and height, optionally lock aspect ratio, then choose how pixels map—Fit (letterbox on white), Cover (center crop to fill), or Stretch. Export as JPEG, PNG, or WebP with a quality slider for lossy formats. Decoding and canvas work stay on your device (no upload). Animated GIFs flatten when exporting to static formats.

Free on-page and technical SEO check for one URL at a time — meta tags, headings, images, links, Open Graph, JSON-LD, and more. We do not include backlinks, keyword rankings, or full-site crawls (those need separate databases). URL mode: server HTML fetch + in-browser audit; optional PageSpeed from Google (capped per browser per day). Paste HTML: 100% in your browser.

Batch-check up to 50 http(s) links: paste one URL per line or extract unique URLs from pasted text/HTML, POST to the link-check API, and see OK, redirect, broken, or timeout with status code, response time, and final URL. Filter and sort the table, export link-check-results.csv in the browser, or re-run checks on broken/timeout URLs only.

Build QR codes in the browser: URL, text, mailto, tel:, SMS (sms:), WhatsApp (wa.me), geo: coordinates, Wi‑Fi join strings, or vCard 3.0. Pick size 128–1024 px, error correction L–H, colors; copy payload, copy PNG, or download PNG/SVG. Tabbed UI with icons; custom strings via Text — no upload.

All-in-one epoch tool in the browser: live second clock, epoch → GMT/local/relative/ISO 8601/RFC 2822 with auto or forced seconds through nanoseconds, date → epoch (YYYY-MM-DD HH:MM:SS style), start/end of year month or day, seconds → duration breakdown, shareable ?t= links, preferences in localStorage, and collapsible code snippets in 25 languages.