# Sunasty

> Free, privacy-first online tools to convert and edit files (images, PDF, video, audio, QR codes) plus developer and date/time utilities — running 100% in your browser. Your files never leave your device: no upload, no server, and everything keeps working offline.

Sunasty runs every operation client-side with JavaScript and WebAssembly. No account, no watermark, no daily limit, and no tracking is required. The interface is available in 28 languages.

## Image tools

- [Resize images](https://sunasty.com/image-resize): Resize and convert your images (JPEG, PNG, WebP) without uploading them.
- [Crop image](https://sunasty.com/image-crop): Crop your images with an interactive preview, drag and resize the crop area. No upload.
- [Add watermark](https://sunasty.com/image-watermark): Overlay a text or image watermark on your photos. Opacity, position, tiling, all in the browser.
- [Rotate & flip images](https://sunasty.com/image-rotate): Rotate images 90/180/270° or flip them horizontally and vertically, without uploading.
- [Redact image regions](https://sunasty.com/image-redact): Blur or black-box sensitive areas of your images before sharing, no upload.
- [Compress images](https://sunasty.com/image-compress): Reduce image file size without uploading. Quality slider or target file size in KB. Batch supported.
- [Convert HEIC to JPG](https://sunasty.com/heic-to-jpg): Convert iPhone HEIC/HEIF photos to JPG or PNG without uploading them.
- [Image to Base64](https://sunasty.com/image-to-base64): Convert images to Base64 data URIs (and back) directly in your browser. Copy, CSS snippet, no upload.
- [Circle crop image](https://sunasty.com/image-circle-crop): Crop any image to a perfect circle with transparent corners. Download as PNG. No upload.
- [Color palette extractor](https://sunasty.com/color-palette): Extract dominant colors from an image as HEX swatches. Copy any color. No upload.
- [Image comparison slider](https://sunasty.com/image-compare): Compare two images side-by-side or with a slider (before/after). No upload.
- [Favicon generator](https://sunasty.com/favicon-generator): Generate favicon PNGs at 16/32/48/180/192/512 px from any image. No upload.
- [Color blindness simulator](https://sunasty.com/color-blindness): Simulate protanopia, deuteranopia, tritanopia and achromatopsia on an image. No upload.
- [SVG optimizer](https://sunasty.com/svg-optimizer): Optimize and minify SVG files with SVGO directly in your browser. No upload.

## PDF tools

- [Merge PDF files](https://sunasty.com/pdf-merge): Combine multiple PDF files into one, directly in your browser.
- [Split PDF](https://sunasty.com/pdf-split): Extract, reorder or delete pages from a PDF without uploading it.
- [Compress PDF](https://sunasty.com/pdf-compress): Reduce PDF file size by losslessly optimizing its internal structure, without uploading.
- [Watermark PDF](https://sunasty.com/pdf-watermark): Add a text or image watermark to every page of a PDF, without uploading.
- [Rotate PDF pages](https://sunasty.com/pdf-rotate): Rotate selected pages of a PDF (90, 180 or 270°) without uploading.
- [Add page numbers](https://sunasty.com/pdf-page-numbers): Add page numbers to every page of a PDF (position, font size, format) without uploading.
- [PDF N-up (pages per sheet)](https://sunasty.com/pdf-nup): Place 2, 4, 6, 8, 9 or 16 PDF pages on each sheet to save paper. 100% in your browser, no upload.
- [PDF metadata remover / editor](https://sunasty.com/pdf-metadata): Remove or edit a PDF's hidden metadata (author, title, software…) in your browser. No upload.
- [Sign a PDF](https://sunasty.com/pdf-sign): Draw your signature and stamp it onto a PDF, directly in your browser. No upload.
- [PDF Editor](https://sunasty.com/pdf-editor): Add text, images, highlights and white-out boxes on top of a PDF, then download. No upload.
- [PDF to images](https://sunasty.com/pdf-to-image): Convert each PDF page to PNG or JPG directly in your browser.
- [PDF to text](https://sunasty.com/pdf-to-text): Extract text content from a PDF and download it as a .txt file, without uploading.
- [Password-protect PDF](https://sunasty.com/pdf-password): Encrypt a PDF with a password directly in your browser. No upload.
- [Unlock PDF (remove password)](https://sunasty.com/pdf-unlock): Remove the password from a PDF you can already open, entirely in your browser. No upload.
- [Crop PDF pages](https://sunasty.com/pdf-crop): Visually crop any PDF page, select a region and apply to all pages or just one, without uploading.
- [Organize PDF pages](https://sunasty.com/pdf-organize): Reorder, rotate or delete pages in a PDF visually, no upload, 100% in your browser.
- [Add PDF Header & Footer](https://sunasty.com/pdf-header-footer): Add custom header and footer text to every page of a PDF, supports {page}, {total} and {date} tokens. 100% in your browser, no upload.
- [Bates Numbering](https://sunasty.com/pdf-bates): Stamp sequential Bates labels (prefix + zero-padded number + suffix) on every page of a PDF. Legal-grade, 100% offline.
- [Resize PDF pages](https://sunasty.com/pdf-resize): Scale every page to A4, Letter, Legal, A3 or A5, or by percentage, without uploading.
- [Flatten PDF](https://sunasty.com/pdf-flatten): Make form fields and annotation appearances permanent (non-editable) in your browser. No upload.
- [Fill PDF forms](https://sunasty.com/pdf-fill): Fill interactive form fields (text, checkboxes, radio, dropdown) in a PDF directly in your browser. No upload.
- [Alternate & Mix two PDFs](https://sunasty.com/pdf-alternate-mix): Interleave pages from two PDFs (A1, B1, A2, B2…) for double-sided scanning. No upload.
- [Extract images from PDF](https://sunasty.com/pdf-extract-images): Pull every embedded image out of a PDF and download them as PNG files, without uploading.
- [PDF to Grayscale](https://sunasty.com/pdf-grayscale): Convert a colour PDF to grayscale entirely in your browser, no upload.
- [Add PDF bookmarks](https://sunasty.com/pdf-bookmarks): Add a clickable bookmark outline (table of contents) to any PDF, define titles, page numbers and nesting. 100% in your browser, no upload.
- [Repair PDF](https://sunasty.com/pdf-repair): Rebuild a damaged or bloated PDF into a clean, well-formed copy, entirely in your browser, no upload.
- [Deskew scanned pages](https://sunasty.com/pdf-deskew): Straighten skewed scanned PDFs or images entirely in your browser, no upload.
- [OCR · image/PDF to text](https://sunasty.com/ocr): Extract text from scanned images or PDFs entirely in your browser, runs offline, no upload.
- [HTML to PDF](https://sunasty.com/html-to-pdf): Convert pasted HTML to a PDF in your browser (best-effort, rasterised). No upload.
- [Images to PDF](https://sunasty.com/image-to-pdf): Combine one or more images (JPG, PNG, WebP) into a single PDF, right in your browser.
- [Word to PDF](https://sunasty.com/word-to-pdf): Convert .docx files to PDF in your browser. Best-effort, complex layouts may differ.

## Video tools

- [Compress video](https://sunasty.com/video-compress): Reduce video file size via in-browser H.264 re-encode. No upload, no server.
- [Merge video files](https://sunasty.com/video-merge): Concatenate multiple video files (MP4, MOV, WebM…) into one. Fast copy or re-encode. No upload.
- [Rotate video](https://sunasty.com/video-rotate): Rotate or flip a video (90°/180°/270°, horizontal/vertical) directly in your browser. No upload.
- [Crop video](https://sunasty.com/video-crop): Crop a video to a rectangle or an aspect ratio (1:1, 16:9, 9:16…) in your browser. No upload.
- [Video converter](https://sunasty.com/video-converter): Convert video between MP4, WebM, MKV and MOV (H.264/H.265/VP9) in your browser. No upload.
- [Add audio to video](https://sunasty.com/add-audio-to-video): Add or replace the soundtrack of a video with an audio file, in your browser. No upload.
- [Screen recorder](https://sunasty.com/screen-recorder): Record your screen in your browser. Nothing is uploaded.
- [Webcam recorder](https://sunasty.com/webcam-recorder): Record your webcam and mic in your browser. Nothing is uploaded.
- [Trim video](https://sunasty.com/video-trim): Cut a video to a start/end time range directly in your browser. Fast stream copy or precise re-encode. No upload.
- [Mute video](https://sunasty.com/video-mute): Remove the audio track from a video (silence it) directly in your browser. No upload.
- [Video to GIF](https://sunasty.com/video-to-gif): Convert a video clip into an animated GIF directly in your browser. No upload.
- [GIF to video (MP4)](https://sunasty.com/gif-to-video): Convert an animated GIF into a small MP4 video directly in your browser. No upload.
- [Extract video frames](https://sunasty.com/video-extract-frames): Extract still frames from a video as PNG or JPG images directly in your browser. No upload.

## Audio tools

- [Audio cutter](https://sunasty.com/audio-cutter): Cut a clip out of an MP3, WAV or M4A right in your browser: fade in/out, ringtone preset. No upload.
- [Audio volume](https://sunasty.com/audio-volume): Boost, reduce or normalize the loudness of an audio file in your browser. No upload.
- [Audio speed](https://sunasty.com/audio-speed): Speed up or slow down audio (0.25×–4×) while keeping the pitch. In your browser, no upload.
- [Reverse audio](https://sunasty.com/audio-reverse): Play an audio file backwards in your browser. No upload.
- [Vocal remover (karaoke)](https://sunasty.com/vocal-remover): Reduce centred vocals to make a karaoke track, in your browser. No upload.
- [MP3 tag editor (ID3)](https://sunasty.com/audio-tags): Edit MP3 ID3 tags (title, artist, album, cover…) in your browser. No upload.
- [Voice recorder](https://sunasty.com/voice-recorder): Record your microphone in your browser. Nothing is uploaded.
- [Audio converter](https://sunasty.com/audio-converter): Convert audio to MP3, WAV or AAC directly in your browser. No upload.
- [Merge audio files](https://sunasty.com/audio-merge): Concatenate multiple audio files (MP3, WAV, M4A, OGG…) into one. Drag to reorder. No upload.
- [Extract audio from MP4](https://sunasty.com/mp4-to-mp3): Extract the audio track from your MP4 videos as MP3, without server-side conversion.

## QR code tools

- [Styled QR code generator](https://sunasty.com/qr-code): Generate beautiful, styled QR codes with custom colors, gradients, shapes and a center logo. 100% local.
- [QR code scanner](https://sunasty.com/qr-scan): Decode a QR code from an image file or your device camera. 100% local, no upload.

## Developer & color tools

- [Archive extractor](https://sunasty.com/archive-extractor): Extract ZIP, RAR, 7z, TAR and GZ archives in your browser. No upload.
- [JSON Formatter](https://sunasty.com/json-formatter): Format, validate and minify JSON directly in your browser. No upload.
- [Base64 Encoder / Decoder](https://sunasty.com/base64): Encode or decode Base64, text and files. No upload, 100% local.
- [URL Encoder / Decoder](https://sunasty.com/url-encoder): Percent-encode or decode URL strings. No upload, 100% local.
- [Hash Generator](https://sunasty.com/hash-generator): Generate MD5, SHA-1, SHA-256, SHA-512 hashes from text or files. No upload.
- [JWT Decoder](https://sunasty.com/jwt-decoder): Decode a JWT (header, payload, expiry) without sending it anywhere. No signature verification.
- [Text Diff](https://sunasty.com/text-diff): Compare two texts line by line and see differences highlighted. No upload.
- [UUID Generator](https://sunasty.com/uuid-generator): Generate cryptographically random UUID v4 values. Bulk generation. No upload.
- [Case Converter](https://sunasty.com/case-converter): Convert text between camelCase, snake_case, kebab-case, Title Case and more. No upload.
- [Text / code viewer](https://sunasty.com/text-viewer): Open text and code files that your phone refuses, Markdown, HTML, JSON, CSV, XML and more.
- [Regex Tester](https://sunasty.com/regex-tester): Test regular expressions against text with highlighted matches and capture groups. No upload.
- [Color Converter](https://sunasty.com/color-converter): Convert colors between HEX, RGB, HSL, HSV and CMYK. WCAG contrast checker included. No upload.
- [Color Scheme Generator](https://sunasty.com/color-scheme): Generate complementary, analogous, triadic, tetradic and monochromatic palettes from a base color. No upload.
- [Timestamp Converter](https://sunasty.com/timestamp-converter): Convert Unix epoch timestamps to human dates (UTC + local) and back. Auto-detects seconds vs milliseconds.
- [Word Counter](https://sunasty.com/word-counter): Count words, characters, sentences, paragraphs and estimate reading time. Live, no upload.
- [Password Generator](https://sunasty.com/password-generator): Generate strong, random passwords with custom rules. Uses crypto.getRandomValues. No upload.
- [Lorem Ipsum Generator](https://sunasty.com/lorem-ipsum): Generate lorem ipsum placeholder text by paragraphs, sentences or words. Copy in one click. No upload.
- [Data Converter](https://sunasty.com/data-converter): Convert data between JSON, YAML and CSV formats. No upload.
- [Minify / Beautify](https://sunasty.com/minify): Minify or beautify HTML, CSS and JavaScript. No upload.
- [AES Encrypt / Decrypt](https://sunasty.com/aes-encrypt): Encrypt or decrypt text using AES-256-GCM. Your passphrase never leaves your browser.

## Date & time tools

- [Date difference](https://sunasty.com/date-difference): Count the days, weeks, months and years between two dates, entirely in your browser, nothing uploaded.
- [Add or subtract dates](https://sunasty.com/date-add): Add or subtract years, months, weeks and days from any date, privately in your browser.
- [Age calculator](https://sunasty.com/age-calculator): Work out an exact age in years, months and days from a birth date, 100% in your browser.
- [Day of the week](https://sunasty.com/day-of-week): Find what day of the week any date falls on, plus day-of-year and week number. Private, offline.
- [ISO week number](https://sunasty.com/week-number): Get the ISO-8601 week number for any date, with the ISO week-year. Private and offline.
- [Leap year checker](https://sunasty.com/leap-year): Check whether any year is a leap year and why, with the nearest leap years. Offline, private.
- [Days until a date](https://sunasty.com/days-until): Count down the days until any date (or how many days ago it was). Private, in-browser.
- [Quarter of a date](https://sunasty.com/quarter-finder): Find which calendar quarter a date belongs to, with the quarter's start and end. Offline.
- [Time since a date](https://sunasty.com/count-up): Count up the time elapsed since a past date, years, months, days and totals. In-browser.
- [Business days calculator](https://sunasty.com/business-days): Count working days (Mon–Fri) between two dates, excluding holidays. Private, in-browser.
- [Time duration calculator](https://sunasty.com/time-duration): Work out the duration between two times of day, including overnight spans. In-browser.
- [Nth weekday finder](https://sunasty.com/nth-weekday): Find the date of the Nth weekday of a month (e.g. the 3rd Monday). Private, offline.
- [Sleep cycle calculator](https://sunasty.com/sleep-calculator): Find the best bedtimes or wake-up times based on 90-minute sleep cycles. In-browser.
- [ISO 8601 duration converter](https://sunasty.com/iso-duration): Parse and convert ISO 8601 durations (P1Y2M…) into components and seconds. In-browser.
- [Date format converter](https://sunasty.com/date-format-converter): Convert a date into ISO, US, European, dotted, compact and Unix formats. In-browser.
- [Cron expression parser](https://sunasty.com/cron-parser): Parse a cron expression and preview its next run times. Private, in-browser.
- [Date details](https://sunasty.com/date-info): Everything about a date: weekday, week, quarter, leap year, zodiac and more. In-browser.
- [Countdown timer](https://sunasty.com/countdown): Count down to any date and time, with a shareable link. Live, private, in-browser.
- [Online timer](https://sunasty.com/timer): A simple countdown timer with a sound alert. No signup, runs in your browser.
- [Online stopwatch](https://sunasty.com/stopwatch): A precise stopwatch with laps. No signup, runs entirely in your browser.
- [Pomodoro timer](https://sunasty.com/pomodoro): Focus with the Pomodoro technique: work/break intervals with sound. In-browser.
- [Timezone converter](https://sunasty.com/timezone-converter): Convert a date and time between any two IANA timezones. No upload, runs entirely in your browser.
- [Timezone difference](https://sunasty.com/timezone-difference): See the current UTC offset difference between any two IANA timezones. Private, in-browser.
- [Timesheet calculator](https://sunasty.com/timesheet): Calculate daily worked hours, totals, overtime and pay from clock-in/out times. Private, offline, no upload.
- [Sunrise & sunset times](https://sunasty.com/sunrise-sunset): Get accurate sunrise, sunset, solar noon and day length for any location and date. Private, offline, no upload.
- [World clock](https://sunasty.com/world-clock): Live local times for cities around the world, side by side. Private, offline, no upload.
- [Moon phase](https://sunasty.com/moon-phase): See the moon phase for any date, its illumination and the next full and new moons. Private, offline, no upload.

## Calculators & converters

- [BMI Calculator](https://sunasty.com/bmi-calculator): Calculate your Body Mass Index instantly, no upload, no server, 100% private.
- [Tip Calculator](https://sunasty.com/tip-calculator): Calculate tip amount, total bill and per-person split instantly, no upload, fully offline.
- [VAT & Tax Calculator](https://sunasty.com/tax-calculator): Add or remove VAT and sales tax instantly. All calculations stay on your device, nothing is uploaded.
- [Fraction Calculator](https://sunasty.com/fraction-calculator): Add, subtract, multiply or divide fractions instantly, results auto-reduced, decimal shown. 100% offline, no upload.
- [Percentage calculator](https://sunasty.com/percentage-calculator): Work out X% of Y, what percent X is of Y, percentage change, and increase/decrease by %. No upload.
- [Cooking converter](https://sunasty.com/cooking-converter): Convert cooking units, cups, grams, ml, oz, by ingredient, plus °F ↔ °C. No upload.
- [Unit converter](https://sunasty.com/unit-converter): Convert length, mass, temperature, volume, area, speed, data and time units. No upload.
- [Currency converter](https://sunasty.com/currency-converter): Convert between 200+ currencies with daily rates, amounts stay in your browser. No upload.
- [Scientific calculator](https://sunasty.com/scientific-calculator): Evaluate expressions with functions, powers and constants, sin, cos, log, √, π. No upload.
- [GPA Calculator](https://sunasty.com/gpa-calculator): Calculate your Grade Point Average instantly, weighted by credits, fully offline. Your data never leaves your device.
- [Grade Calculator](https://sunasty.com/grade-calculator): Calculate your weighted average grade and find out what score you need on your final exam.
- [Running Pace Calculator](https://sunasty.com/pace-calculator): Calculate your running pace, time or distance instantly in your browser - no upload, 100% private.
- [Loan Calculator](https://sunasty.com/loan-calculator): Calculate monthly payments, total cost and interest for any fixed-rate loan. 100% offline, no data leaves your device.
- [Compound & Simple Interest Calculator](https://sunasty.com/compound-interest-calculator): Calculate compound or simple interest on any investment or loan, fully offline, nothing leaves your device.
- [Random Number Generator](https://sunasty.com/random-number-generator): Generate random integers in any range, secure, offline, and private.
- [Calorie Calculator](https://sunasty.com/calorie-calculator): Calculate your BMR and TDEE to find daily calorie needs for weight loss, maintenance, or gain, 100% private, no upload.
- [Mortgage Calculator](https://sunasty.com/mortgage-calculator): Estimate your monthly mortgage payment (principal, interest, tax, insurance, PMI), 100% private, no upload.
- [Body Fat & Ideal Weight Calculator](https://sunasty.com/body-fat-calculator): Estimate your body fat percentage and ideal weight instantly, US Navy method, 100% offline, no data leaves your device.

## Privacy & metadata tools

- [Remove PDF annotations](https://sunasty.com/pdf-remove-annotations): Strip comments, highlights, links and form fields from a PDF without uploading. Privacy-safe.
- [Read EXIF metadata](https://sunasty.com/exif-reader): View and strip EXIF metadata from your photos without sending them to a server.
- [Content Credentials (C2PA) reader](https://sunasty.com/c2pa-reader): Read the C2PA / Content Credentials provenance of an image or file in your browser. No upload.
- [Office metadata remover](https://sunasty.com/office-metadata): Remove the hidden document properties (author, company, dates…) from Word, Excel and PowerPoint files. 100% in your browser, no upload.

## Optional

- [All tools (searchable index)](https://sunasty.com/tools)
- [Sitemap](https://sunasty.com/sitemap-index.xml)