Find a tool, get it done

Add page numbers to a PDF and see them land before you commit: five formats, nine positions, any start number, and a cover you can leave bare. The preview restamps as you tweak.

Add subtitles to a video permanently. Load an SRT or VTT, or let Whisper write one from the speech, then style the captions on a live preview and export an MP4 with the words on every frame.

Add a watermark to a photo: text or a logo, dragged wherever you want it or tiled diagonally across the frame, then repeated over a whole folder at once.

An age calculator that counts whole calendar months, so it answers 34 years, 2 months, 5 days, then repeats the same span in months, weeks and days.

An alt text generator that looks at the photo and writes the first draft, using Microsoft's Florence-2.

Audio transcription with Whisper. Drop in a recording and get editable text, plus SRT and WebVTT carrying timestamps, from any of four model sizes.

Remove the background from a photo and keep a transparent PNG, or set the cut-out on a solid color as a JPEG. It finds the subject itself, or you tap or circle the one you want.

Blur, pixelate or black out faces in a photo. A small detector boxes the faces it finds, small ones in a group included, and you box whatever it misses.

AI image upscaler that enlarges a photo 2× or 4×, or works back from the exact print size you type in. Rebuilds detail instead of stretching pixels.

Remove a photobomber, a bin or a stray cable from a photo. Tap it, circle it or paint over it, see how much of the frame it takes, and MI-GAN fills the gap.

Extract text from an image or a scanned PDF, using a neural engine that reads 50 scripts and copes with a page shot at an angle.

Paraphrase text four ways: formal, casual, shorter, or longer, with a small language model that does the rewriting on your own graphics card.

Summarize a long article, an email thread, or a report down to a few sentences. Pick short, medium, or long; the AI model downloads once and then works offline.

A video subtitle generator built on Whisper. Feed it an MP4 and get SRT, WebVTT or a plain transcript, with cues capped at two lines of 42 characters.

A vocal remover that splits a song into two stereo tracks, the voice on one and the instrumental on the other, using Deezer's Spleeter model.

An online alarm clock for any time you type, or one of eight common wake-ups: four sounds, a five-minute snooze, a fullscreen bedside face, and it survives a refresh.

A REST client in a tab: build the request, press Send, and when a call gets blocked, read the CORS reason in words plus a server snippet.

An APR calculator that folds up-front fees back into the rate. Borrow 25,000 at 7.5% over 60 months with a 500 origination fee and the true annual cost is 8.36%, on a payment of 500.95.

A batch audio converter: load MP3, WAV, M4A, OGG or FLAC in any mix, queue as many as you like, and write M4A, WAV, Opus or FLAC back out with a zip at the end.

An audio cutter that keeps every part you mark and throws away whatever falls between them, fades and crossfades included.

An audio joiner for stitching clips into one track: queue them in order, set a crossfade if you want them to blend, then export M4A, WAV, Opus, or FLAC.

Normalize audio by its loudest peak: see the lift in decibels before you press, pick a headroom preset, and download a copy that lands on the target.

Reverse audio end to end and hear it play backwards, then save the flipped clip as M4A, Opus, WAV, or FLAC. Sample rate and pitch stay exactly where they were.

Change audio speed anywhere from 0.5x to 2x: drop a track to 0.75x for a slowed edit, or lift it to 1.5x for nightcore. Pitch follows the speed. Exports as M4A, WAV, Opus or FLAC.

An audio visualizer that splits whatever's playing into 1,024 frequency bands and draws each one as a bar, updated every frame.

Barcode generator and reader for Code 128, EAN-13, UPC-A, EAN-8, Code 39, ITF-14 and Codabar. Check digits are worked out for you. Download SVG or PNG, batch a list of 200, or read a code off a photo.

Base64 encode text or decode it back, UTF-8 clean, so emoji and accented letters survive the round trip. Files go in too, with an optional data: URI wrapper.

Hash a password with bcrypt at any cost factor from 4 to 31, or paste an existing $2a$, $2b$ or $2y$ hash and check a password against it. The cost and salt are read out of the hash.

A bill splitter for one check or a whole trip: tip, tax, who paid what, and the shortest list of transfers that squares everyone up.

A BMI calculator that puts your reading on a 15-to-40 scale beside the WHO cut-offs, then works backwards to the weights that count as healthy at your height.

BPM counter with two ways to get an answer: analyze an audio file, or tap the beat out yourself. File detection always lands between 90 and 180 BPM.

A calorie calculator built on Mifflin–St Jeor: your maintenance number, the BMR under it, and loss or gain targets at 250 and 500 kcal, plus a date if you name a goal weight.

A case converter that answers ten ways at once: UPPERCASE, lowercase, Title Case, Smart Title Case, Sentence case, camelCase, PascalCase, snake_case, kebab-case, CONSTANT_CASE.

Chat with a PDF in ordinary words. Answers cite the page and show a snapshot of the passage they came from.

A color converter that reads hex, CSS names, rgb(), hsl() and oklch(), and writes each one back with CMYK and the nearest named color.

A color palette generator that starts from one colour you trust, typed or lifted from a photo, and returns five named colours for a site, shown in use and ready to paste.

Compound interest calculator for savings, an FD or an RD: future value, how much of that is interest, and a year-by-year schedule.

Compress a PDF by re-encoding the pictures inside it, down to a KB ceiling if a form demands one. Text stays sharp.

Countdown timer with quick presets and an alarm that keeps beeping until you stop it. Set anything up to 99:59:59 and the tab title tracks the time left.

Countdown to any date. How many days until a birthday, a holiday or a deadline, counted down to the second.

Paste a cron expression and read it back in plain English, column by column, with the next five run times in UTC, your own zone or the server's.

Crop a PDF by dragging a box or typing margins in millimetres. Fit to content finds the ink, sideways pages are cut on the right edge, and any page can keep its own box.

A CSS box shadow generator with real sliders: offset, blur, spread and color on every layer, an inset toggle, a live preview card, and one button that copies the declaration.

A CSS gradient generator with a live preview: pick linear, radial or conic, stack up as many color stops as you want, then copy the value into a background rule.

CSV to XLSX or an Excel sheet back out as CSV, with the separator read from the data and a wrong split refused before it reaches a workbook. Every cell stays text.

A CSV viewer that reads the delimiter off the file and shows its working, types every column so prices sort by value, and downloads the filtered view under the file's own name.

Convert a curl command to code for 30 targets, including seven separate Node.js HTTP clients.

A currency converter built on the European Central Bank's daily reference rates: 30 currencies, cross-rated through the euro, with the publication date printed under every result.

A date calculator for questions like what date is 90 days from today. Add or subtract days, weeks, months or years, and get the weekday with the answer.

Days between two dates, with the same span given in weeks, in years and months, and in business days once your own holidays come out.

A debt payoff calculator that runs snowball and avalanche month by month, then reports your debt-free date, the total interest, and the order your balances clear.

Scan paper with a phone camera and get back a straight, readable multi-page PDF: auto edge detection, per-page looks, a stain eraser, optional searchable text.

DOCX to HTML with semantic tags and none of Word's span soup. Preview it, copy the markup, or save a styled standalone page.

Convert DOCX to Markdown with ATX headings, hyphen bullets, working links and GFM pipe tables. Copy the output or save it as a .md file under the original name.

Convert a .docx to text and keep only the words, with Word's fonts and spacing left behind. Copy the result or save a .txt that keeps the document's name.

An email signature generator that outputs a single inline-styled HTML table, previewed live, ready to paste into Gmail or Outlook as rich text.

Excel to PDF for a workbook someone only needs to read: tick the sheets worth sending, choose A4 or US Letter, portrait or landscape, and each sheet lands as its own page of selectable text.

An EXIF viewer for JPEGs and PNGs that lists every block a clean copy removes (EXIF, XMP, IPTC, PNG text), keeps GPS on the page, and rewrites nine fields.

Extract audio from a video and keep the soundtrack on its own. AAC inside an MP4 is copied across without re-encoding, so the M4A you get back holds the original track untouched.

Favicon generator: one image in, a package out. Six PNGs, a multi-size favicon.ico, a manifest with your colours, the head tags, and the 16 seen in a real tab.

Encrypt a file behind a password with AES-256-GCM and get back a .tray you can open on any machine. The key is stretched with PBKDF2 at 600,000 iterations.

Fill and sign a PDF, or click a line of printed text and retype it. Whiteout, highlight, shapes and a signature you draw, type or upload sit in one toolbar.

Flatten a filled PDF form so the answers become part of the page. Every field is listed first, and the ones that cannot be baked, like an empty signature, are named.

A grade calculator with four switchable modes: GPA on the 4.0 scale, CGPA to percentage, a weighted class grade, and what you still need on the final.

Hash generator for MD5, SHA-1, SHA-256, SHA-384, SHA-512 and CRC32, plus keyed HMAC and a compare box that says outright whether two checksums match.

A mortgage calculator that adds up the whole payment: principal and interest, property tax, home insurance and PMI, with the month the insurance ends and a CSV of every month.

Convert HTML to Markdown, or render Markdown back to HTML, with the result redrawing as you type. Turndown handles one direction, markdown-it the other, and GFM tables survive both.

An HTML entity encoder and decoder in one box: escape & < > " and ', or fold entities back into plain characters.

Edit an MP3's ID3 tags and cover art: title, artist, album, genre, year and the picture, with every other frame carried through. Fix Unknown Artist.

An image color picker with a magnifier: hover to zoom in on the pixels, click the one you want, and copy its HEX, RGB or HSL code.

Compress a JPEG, PNG or WebP and compare it side by side. Smart picks the quality, Quality takes a slider, Target searches for a size in KB. One file or a folder.

Image converter that writes AVIF, WebP, JPEG, or PNG with the WebAssembly codecs from Squoosh, and reads iPhone HEIC, TIFF, JPEG XL and SVG going in.

Crop an image to 1:1, 16:9, 9:16 or a ratio you type in, with the cut taken from the full-resolution file rather than the preview on screen.

Resize an image by width, percent, a KB budget or a print size in millimetres. The preview and the pixel counts redraw as you type.

Convert an image to Base64 and copy it four ways: the data URI, a ready-made <img> tag, a background-image rule, or the bare payload. PNG, JPEG, GIF, WebP and SVG all encode.

Image to PDF for JPGs, PNGs and phone photos: one picture per page or stacked, A4 or Letter, in the order you drag them, with the PDF shown before you save it.

Convert an image to SVG with the vtracer engine. Three tracing presets, five manual sliders, and a shape count under the result that tells you how heavy it is.

A JSON diff that parses both sides before it compares them, so reordered keys count for nothing and every real change arrives as a key path like items[2].price.

A JSON formatter with a validator attached: indent at 2 or 4 spaces, minify to one line, or fold a huge payload into a tree.

Turn a JSON sample into TypeScript interfaces, or switch the output to Go structs with json tags, Zod schemas, or Pydantic models. Name the root type and the nested ones follow it.

A JWT decoder that splits a token into its three segments, turns iat and exp into readable UTC times, and checks the signature against a secret or public key you paste.

Spreadsheet column in, comma-separated list out, or the reverse. De-duplicate, sort and quote every value on the way through.

A loan EMI calculator: the monthly payment, the total interest sitting beside it, and every month of the schedule.

A lorem ipsum generator drawing on a 63-word Latin bank, with sentences of 5 to 14 words and up to 100 units per run.

A Markdown table generator for CSV or spreadsheet rows. Paste them in, the first line becomes the header, and the output is padded so columns line up in the raw text too.

Markdown to HTML with the rendered page beside the source. Pipe tables, 36 highlighted languages, Mermaid diagrams, and a markdown.html download.

Markdown to PDF that keeps the text selectable and searchable. A4 pages, an 11pt body, code on a light grey panel, links still clickable.

Markdown to Word, done properly: paste your notes and download a real .docx that Word, Google Docs or Pages will edit. Headings map onto Word's own Heading 1 to 6, code lands in Courier New.

Merge PDF files into one document in the order you set, with each file's bookmarks and filled form fields carried across and a bookmark added for every file.

Merge videos into one MP4 or WebM. Seven transitions plus a plain cut sit at every join, and each clip can be trimmed before it renders.

A meta tag generator for link previews: nine fields in, up to fifteen lines of head markup out, with the share card and the search result they make drawn above the fields.

A mock data generator for test tables: names, emails, UUIDs, timestamps and prices, up to 1,000 rows a run. Export as JSON, CSV or SQL INSERTs, and set a seed when the rows have to repeat.

Stereo to mono, or mono to stereo: pick a direction and get the file back as M4A, Opus, WAV, or FLAC.

Morse code translator that runs both ways, on 54 characters of the international table, with a Play button that beeps the result at 15 words per minute.

Mute a video by dropping its audio tracks while the picture is copied across without re-encoding, so a two-minute clip finishes in seconds and the frames come back identical.

Number base converter for binary, octal, decimal and hex, reading input written in any base from 2 to 36. BigInt math, so a 128-bit value converts exactly.

An online notepad that keeps markdown notes in folders, links them with [[double brackets]], and autosaves four tenths of a second after you stop typing.

Organize PDF pages as a grid of thumbnails you can drag: rotate a sideways scan a quarter turn, duplicate a page, drop the cover sheet, or append a second file, then save it.

A Parquet viewer that edits as well as reads. Open a .parquet file, walk its schema, page through ten million rows, change a cell, then save real Parquet or export the view as CSV.

A passport size photo maker with ten document presets, from the US 2×2 inch to China's 33×48 mm, plus a head-and-eye guide and a 4×6 print sheet at 300 DPI.

Password generator with two modes: random strings from an 80-character pool, or EFF wordlist passphrases that print their entropy in bits. Length runs to 256, batches up to 100.

Convert PDF to JPG or PNG at 1x, 2x or 3x resolution, one image per page. Narrow it to a range like 1-3, 5 and take the results singly or as one ZIP.

Extract text from a PDF the moment it lands, copy it or save a .txt named after the file, and see which pages are scans with no text to give.

Convert a PDF to an editable Word .docx that keeps its columns, ruled tables, headings and pictures, or switch to Exact layout and pin every line to the coordinates the page gave it.

A percentage calculator that answers four questions on one page: X% of a number, X as a percent of Y, the increase or decrease between two figures, and what a price drops to after a discount.

A pomodoro timer with a task list. Twenty-five minutes of focus, five off, a long break every fourth round, and every finished session counted against what you're working on.

Password protect a PDF with AES-256 encryption from qpdf, then decide under Terms whether whoever receives the file may print the document, copy text out of it, or edit it at all.

A QR code generator that writes your data straight into the modules rather than a redirect link that can expire. Eight payload types, PNG or SVG, 200 at a time.

Redact a PDF for real: drag a black box over a name, and that page comes back as an image with the text underneath deleted.

A regex tester that reads the pattern back to you in plain English as it highlights every match and group.

Remove background noise from audio with DeepFilterNet, a speech model that runs on your device. Hum, fans and hiss drop away, the voice stays, and the clean take saves as M4A, WAV, Opus or FLAC.

Rotate PDF pages 90° or 180° and download a file that opens the right way up in every reader. Turn all of them or just a few.

Salary to hourly, or hourly back to salary: type one figure, mark which period it belongs to, and the other four fill themselves in.

An online scientific calculator you write expressions into instead of tapping key by key: trig in degrees or radians, logs, powers, factorials, and exact answers like 2/3 + 3/4 = 1 5/12.

Remove silence from audio automatically. Two numbers decide what goes: how quiet a gap has to be, and how long it has to last.

A SIP calculator that splits the maturity figure into the money you paid in and the money it earned, with a year-by-year table under the chart.

JSON to CSV with the header row built from your keys, or CSV back to JSON with numbers, booleans and nested objects restored.

Split a PDF by page range, pull out a single page, drop the ones you don't want, or burst one long file into a numbered set that downloads as a zip.

Compare two Excel or Google Sheets ranges by pasting them side by side. Changed cells light up, added rows go green, removed rows red.

SQL playground running a real SQLite engine: query a sample schema or open your own .sqlite file, then pretty-print the query in any of eleven dialects.

An online stopwatch that counts in hundredths, records laps into a Lap/Split/Total table, exports them as CSV, and runs from the Space and L keys.

JSON escape and unescape, plus JavaScript literals, \uXXXX Unicode and backslash sequences. Four modes, both directions.

A subnet calculator for IPv4 and IPv6 that reads a CIDR or an address and mask as you type. Network and broadcast, mask and wildcard, usable host range, plus ip6.arpa and EUI-64 for v6.

Convert SRT to VTT and back, retime cues that drift out of sync, and fix the wording in an editable table of every line.

A text cleaner for pasted mess: pull the hard line breaks out of PDF copy, squash double spaces, thin the blank lines, and swap curly quotes for straight ones.

Text to speech two ways: the voices your device already has, or a 13-voice English model that hands you a file.

A text and code diff checker that goes down to the word: edited lines show only the parts that actually changed, and the comparison exports as a unified .diff.

A time duration calculator for the gap between two clock times. Enter start and end, take off an unpaid break, and read it as 8h 0m, 8.00 decimal hours, or 480 minutes.

A tone generator that sounds the moment you press Play: type or slide to any frequency, sweep 20 Hz to 20 kHz, or play white, pink and brown noise.

Trim a video down to the part worth keeping, or lift several pieces out of one recording and join them. Pull only the end handle in and nothing goes through the encoder.

A unit converter with 19 categories, from cm to inches and kg to lbs through pressure, torque and data rate. Pick two units and read the answer as you type.

Turn a Unix timestamp into a readable date or a date back into epoch seconds. Auto-detect sorts 10-digit from 13-digit.

Remove the password from a PDF, or lift the owner restrictions that grey out printing and copying. Type the open password once and unlock a whole batch.

A URL encoder and decoder with the encodeURIComponent versus encodeURI choice made explicit: Component escapes / and & inside a query value, Full URL leaves them standing.

UUID generator for v4, v7 and ULID, up to 1000 ids per press. v4 is 122 random bits; v7 and ULID sort by creation time.

Compress a video to a size you type in MB and see the projected file before encoding, with presets for WhatsApp at 64, email at 25 and Discord at 20.

Convert video between MP4, MOV, MKV and WebM in your browser. Each target says first whether the clip is repackaged untouched or re-encoded.

Convert a video to a looping GIF at 10 to 24 fps and the width you choose, with a preview that plays before you save.

A voice recorder with a real pause: hold the take, breathe, carry on into the same file. Live input meter, a mic picker when you have more than one, and M4A, WAV, Opus or FLAC out.

Add a watermark to a PDF: type CONFIDENTIAL or drop in a logo, place it on a grid of the page or drag it by hand, and see the real stamped page before you download.

Enter two hex colors and get the WCAG contrast ratio, four pass/fail badges covering AA and AAA at both text sizes, and a live preview at 16px and 24px.

The ISO 8601 week number for today or any date you pick, with the day of the year, the weeks left in it, and that week's Monday and Sunday.

A word counter that also tells you when you have run long. Words, characters, sentences and reading time, plus live checks against the 280, 160, 70 and 60-character caps that cut text off.

Word to PDF without opening Office. Give it a .docx and you get back an A4 document with selectable text and links that still click.

A world clock and time zone converter with a meeting planner that finds the hour everyone is at work, then copies the slot in each city's own local time.

An XML formatter and validator that also converts XML to JSON and back, with errors pinned to the line.

Convert YAML to JSON, or JSON back to YAML. Output comes back pretty-printed at two-space indent, and a manifest that won't parse gets an error naming the line.

Zip files and folders into one archive with the subfolder paths kept, put an AES-256 password on it if it needs one, or open a .zip and pull out the entry you wanted.