27 tools, grouped below.
Page-level work on files you already have: combining them, pulling pages out, stamping them, or producing a document you can send to a client. Nothing is uploaded — the PDF is read and rewritten in the tab.
Merge, split, rotate, watermark and convert PDF files entirely in your browser.
Build and export a clean freelance invoice or quotation as a PDF, in your own country's labels and currency, with data kept on your device.
Editing, converting and cleaning up pictures. The browser decodes and re-encodes the file on your device, which also means the size limit is your own memory rather than an upload cap.
Crop, adjust, annotate and draw on images without uploading them anywhere.
Convert between PNG, JPEG and WebP and shrink file size in your browser.
Inspect and strip EXIF, GPS and other metadata before you share a photo.
Resize and crop images to the aspect ratios social platforms expect.
Working with media files and the caption tracks that go with them. Two tools here reach the network by design, and each says which host it contacts before it contacts it.
Download a media file from a direct link, straight to your device, with the URL checked before anything is contacted.
Convert, retime and clean SRT and VTT subtitle files in your browser.
Pull every thumbnail size and the public title, channel and embed details for a YouTube link.
Tabular and numeric work: repairing an export that will not open cleanly, and modelling figures you type yourself. No market data is fetched and no file is sent anywhere.
Educational discounted cash flow model driven entirely by your own assumptions.
Tidy delimiters, headers, duplicates and encodings in spreadsheet exports.
Small jobs that are awkward everywhere else — reshaping a block of text, counting it, or turning a link into something scannable.
Generate QR codes and Code 128 barcodes without a server round trip.
Case conversion, diffing, counting, escaping and whitespace cleanup for text.
The utilities you reach for mid-task: converting between formats, decoding a value, or working out a permission bit or a cron field. All of them are panels inside one product, so switching between them costs no page load.
Pretty-print with the indent you want, or get the exact line and column where a document stops being valid.
JSON to YAML is my favorite of the bunch
Round-trips UTF-8 correctly, so accents, CJK and emoji come back exactly as they went in.
Percent-encode a single query value or a whole address, with the encodeURI and encodeURIComponent difference spelled out.
Turn markup into text you can paste anywhere. Decoded with a lookup table rather than the HTML parser, so your input stays data.
Read an epoch value in seconds or milliseconds, in UTC and your local zone, with the unit always stated rather than guessed.
Identifiers from the browser’s cryptographically secure generator — never Math.random() — plus a check that a given string is well formed.
SHA-1, SHA-256, SHA-384 and SHA-512, computed by the browser’s own Web Crypto implementation.
Spot what changed between two versions line by line, with case and whitespace differences optionally ignored.
Inspect the header and payload of a token. Decode only: the signature is never verified, so nothing shown here proves a token is genuine.
Perfect for web devs
Simplify Chmod permissions with this cheatsheet
To save Docker run parameters as config files
The be-all-and-end-all tool for Cron automation