Free online tools that work in your browser
PDF, image, text and calculation tools that run on your device instead of on our servers. No uploads, no sign-up, no watermarks.
11 of 44 tools live — more added every week.
Categories
PDF Tools
Merge, split, compress, rotate and convert PDF files without uploading them to a server.
8 toolsImage Tools
Compress, resize, crop and convert images right in your browser, with no quality surprises.
9 toolsText Tools
Count, clean, format and compare text — from word counts to JSON formatting and diffs.
8 toolsConverters & Calculators
Everyday unit, date and money maths: unit conversion, age, BMI, loan EMI and more.
8 toolsSecurity & Encoding
Generate passwords, hashes, QR codes and barcodes, and encode or decode text safely offline.
6 toolsDesign & Dev Utilities
Colour, gradient, regex and code-formatting helpers for designers and developers.
5 toolsAll tools
PDF Tools
View categoryPDF Viewer
Open and read a PDF full screen in your browser, with dark mode, without it being uploaded anywhere.
Merge PDF
Combine several PDFs into one file and drag the pages into the order you want before merging.
Split PDF
Pull out a page range or split every page of a PDF into its own separate file.
Compress PDF
Shrink a PDF by re-encoding the images inside it, with a quality setting you control.
PDF to Image
Export each page of a PDF as a JPG or PNG image file.
Image to PDF
Turn one or many images into a single, tidy PDF document.
Rotate & Reorder PDF Pages
Rotate individual pages or drag them into a new order, then export the fixed PDF.
Add Watermark & Page Numbers
Overlay a text watermark on a PDF, or stamp automatic page numbers, with full control over position and opacity.
Image Tools
View categoryImage Compressor
Cut image file size with a quality slider and a side-by-side before/after preview.
Image Resizer
Resize an image by pixels or percentage, with an optional lock on the aspect ratio.
Image Format Converter
Convert images between PNG, JPG, WebP and GIF in a couple of clicks.
HEIC to JPG
Convert HEIC photos straight off your iPhone into JPGs that open anywhere.
Background Remover
Strip the background out of a photo using a machine-learning model that runs in your browser.
Image Cropper
Crop freehand or to a fixed ratio, with a live preview of the result.
Passport & ID Photo Maker
Crop and resize a photo to official passport or visa dimensions, with Nepal, India, US and Schengen presets.
Favicon Generator
Build a complete favicon set — .ico plus every PNG size you need — from one image.
Image to Base64
Convert an image file into a Base64 string, or decode a string back into an image.
Text Tools
View categoryWord & Character Counter
Live counts for words, characters, sentences, paragraphs and estimated reading time.
Case Converter
Switch text between UPPERCASE, lowercase, Title Case, Sentence case, camelCase and snake_case.
JSON Formatter & Validator
Pretty-print or minify JSON and get the exact line and column of any syntax error.
Lorem Ipsum Generator
Generate placeholder paragraphs, sentences, words or list items on demand.
Text Diff Checker
Compare two blocks of text side by side with additions and deletions highlighted.
Markdown to HTML
Write Markdown on the left, get clean HTML and a live preview on the right.
Duplicate Line Remover
Strip repeated lines from a list, with an optional case-sensitivity toggle.
Text Reverser
Reverse a whole block of text, or just the order of its words or lines.
Converters & Calculators
View categoryUnit Converter
Convert length, weight, temperature, volume and area between metric and imperial units.
Currency Converter
Convert between world currencies using live exchange rates.
Age Calculator
Work out an exact age in years, months and days from any date of birth.
BMI Calculator
Calculate body mass index and see the matching category, in metric or imperial units.
EMI & Loan Calculator
Find the monthly payment on a loan and read the full amortisation schedule.
Percentage Calculator
Several percentage modes in one place: of a number, increase, decrease and difference.
Date Difference Calculator
Count the days, weeks and months between any two dates.
Time Zone Converter
Convert a time across zones and find a meeting slot that works for everyone.
Security & Encoding
View categoryPassword Generator
Create strong random passwords with your own length and character rules, plus a strength meter.
Base64 Encode & Decode
Encode or decode Base64 for both plain text and files.
URL Encode & Decode
Percent-encode or decode URLs and individual query-string components.
Hash Generator
Produce MD5, SHA-1 and SHA-256 hashes from text or from a file.
QR Code Generator
Make QR codes for links, plain text, WiFi logins or contact cards, and download them as PNG or SVG.
Barcode Generator
Generate CODE128, EAN and other common barcode formats as downloadable images.
Design & Dev Utilities
View categoryColour Picker & Palette Generator
Pick a colour and generate complementary, analogous and triadic palettes from it.
Colour Code Converter
Convert a colour between HEX, RGB and HSL notation.
CSS Gradient Generator
Build a gradient visually and copy the ready-to-paste CSS straight out of the preview.
Regex Tester
Test a regular expression against sample text with live match highlighting and an explanation.
Minifier & Beautifier
Minify or pretty-print CSS, JavaScript and HTML.
Why ToolStash is different
Nothing is uploaded
Files are processed by your own browser using JavaScript and WebAssembly. They never travel to a server, so there is nothing for us to store, leak or sell.
No account, no limits
No sign-up, no email, no daily cap on how many files you can process. Open the page, do the job, close the tab.
Works offline once loaded
Because the work happens locally, most tools keep working even if your connection drops mid-task.