Free online tools for the small jobs, right in your browser
Forty free tools for SEO, writing, images, PDFs, everyday calculations and code. Type what you need below. Your text and files are processed on your own device, not uploaded.
Built to be useful, not just quick
Every tool does real work
Each tool produces an actual result you can copy or download. There are no sample outputs, no locked premium features and no buttons that lead nowhere.
Your files stay with you
Text, images and PDFs are processed by your browser, on your device. The tools are designed so that the content you enter never needs to reach a server.
Explanations, not just inputs
Every tool page explains how the tool works, walks through an example and lists its limitations, so you know when to rely on the result and when to double-check it.
Browse the toolbox
Filter by category or type what you need. Every tool opens on its own page.
40 tools
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Meta Tag Analyzer
Audit titles, descriptions, canonicals, Open Graph and more from page HTML. -
SERP Snippet Preview Tool
See how a title and description may look in search results. -
Keyword Clustering Tool
Group a keyword list into topic clusters by shared words. -
Robots.txt Generator
Build a robots.txt file and test paths against its rules. -
XML Sitemap Builder
Turn a list of URLs into a valid sitemap.xml file. -
UTM Link Builder
Add correctly encoded UTM campaign parameters to any link. -
Keyword Density Checker
Count how often words and phrases appear in a piece of text. -
Internal Link Planner
Plan which pages should link to each other, with anchor text. -
Word Counter
Count words, characters, sentences and paragraphs as you type. -
Case Converter
Switch text between sentence, title, upper, lower and code cases. -
Duplicate Line Remover
Remove repeated lines from a list and optionally sort it. -
Find and Replace Tool
Replace words or patterns throughout a text, with regex support. -
Lorem Ipsum Generator
Generate placeholder text as paragraphs, sentences, words or lists. -
Text Diff Checker
Compare two versions of a text and highlight the differences. -
URL Slug Generator
Convert titles into clean, readable URL slugs. -
Reading Time Calculator
Estimate how long a text takes to read or to speak aloud. -
Image Compressor
Shrink image file sizes with adjustable quality, without uploading. -
Image Resizer
Change an image’s width and height, keeping proportions if you like. -
Image Format Converter
Convert images between JPG, PNG and WebP formats. -
Image Cropper
Crop an image to an exact area or aspect ratio. -
Image Color Picker
Pick exact HEX, RGB and HSL colours from any pixel of an image. -
QR Code Generator
Create QR codes for links, Wi-Fi, contacts and more; download PNG or SVG. -
PDF Merger and Splitter
Combine PDFs into one file, or extract and split pages. -
PDF to Image Converter
Render PDF pages as PNG or JPG images at the resolution you need. -
Percentage Calculator
Solve the five most common percentage questions, with formulas. -
Discount Calculator
Work out sale prices, savings, stacked discounts and tax. -
Profit Margin Calculator
Find margin, markup and the selling price that hits your target. -
Age Calculator
Find an exact age in years, months and days on any date. -
Date Difference Calculator
Count days and working days between dates, or add days to a date. -
Unit Converter
Convert length, weight, temperature, volume, data and more. -
BMI Calculator
Calculate adult body mass index in metric or imperial units. -
Compound Interest Calculator
Project how savings grow with compound interest and deposits. -
JSON Formatter and Validator
Pretty-print, minify and validate JSON with exact error locations. -
Base64 Encoder and Decoder
Encode and decode Base64 for text and files, including URL-safe Base64. -
URL Encoder and Decoder
Percent-encode and decode URLs, and inspect their parts. -
Hash Generator
Create MD5 and SHA hashes of text or files and verify checksums. -
UUID Generator
Generate v4 and v7 UUIDs in bulk and inspect existing ones. -
Regex Tester
Test regular expressions with live highlighting and capture groups. -
HTML, CSS and JavaScript Minifier
Shrink HTML, CSS and JavaScript by removing what browsers do not need. -
Password Generator
Generate strong random passwords with cryptographic randomness.
No tools match that search. Try a shorter word, such as “pdf” or “case”, or see the full directory.
Five categories, forty tools
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SEO & Digital Marketing Tools
Check metadata, preview snippets, plan keywords and build crawl files.
8 tools
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Text & Writing Tools
Count, clean, compare and reshape text without leaving the page.
8 tools
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Image & File Tools
Compress, resize, convert and crop images; merge, split and render PDFs.
8 tools
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Online Calculators & Converters
Percentages, prices, margins, dates, units, BMI and compound interest.
8 tools
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Developer Tools
Format JSON, encode data, hash strings, test regex and minify code.
8 tools
Editor’s picks
A starting selection made by our editors because these tools cover very common tasks. It is not based on usage statistics — we do not publish popularity rankings.
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Word Counter
Count words, characters, sentences and paragraphs as you type. -
Image Compressor
Shrink image file sizes with adjustable quality, without uploading. -
JSON Formatter and Validator
Pretty-print, minify and validate JSON with exact error locations. -
PDF Merger and Splitter
Combine PDFs into one file, or extract and split pages. -
SERP Snippet Preview Tool
See how a title and description may look in search results. -
Percentage Calculator
Solve the five most common percentage questions, with formulas. -
QR Code Generator
Create QR codes for links, Wi-Fi, contacts and more; download PNG or SVG. -
Password Generator
Generate strong random passwords with cryptographic randomness.
Popular guides
Step-by-step help for common jobs, with worked examples. See all 40 guides
How to Compress an Image to 100KB (or Any Size Limit) Without Uploading It
Reduce a JPG, PNG or WebP photo to 100KB, 50KB or any size limit in your browser. Step-by-step settings that work, with no upload and no sign-up.
How to Merge PDF Files Without Uploading Them
Combine PDFs into one document in any order, include only certain pages, or split a PDF into separate files, all in your browser so private files stay private.
How to Calculate Percentages: Formulas and Examples
Simple formulas for percentage of a number, what percent one number is of another, percentage increase and decrease, and reversing a percentage, with examples.
Margin vs Markup: What’s the Difference and How to Calculate Both
Profit margin and markup explained with formulas and examples, a conversion table, and how to set a selling price that hits your target margin after fees.
How to Create a QR Code for a Link, Wi-Fi or Contact Card
Make a free QR code for a website, Wi-Fi password, phone number, text message, email or contact card that never expires, and print it so it scans reliably.
Title Tag and Meta Description Length: How to Avoid Being Cut Off
Why search results cut titles and descriptions by pixel width, not characters, and how to write snippets that display in full on desktop and mobile.
How it works
Find the tool
Search above or browse by category. Each tool has its own page with a short explanation of what it does.
Add your input
Paste text, type numbers or choose a file. Files are opened by your browser; they are not sent anywhere.
Use the result
Copy the output, download the file or adjust the settings and run it again. Nothing is saved after you leave the page.
Private by design
The tools on this site are written in JavaScript that runs in your browser. When you compress an image, merge PDFs or format JSON, the work happens on your computer or phone, and the result is created there too. Closing the tab discards it.
Visiting any website still involves some data: your browser requests the pages from our host, and the theme you choose is remembered in your browser's local storage. The privacy policy lists exactly what is collected and by whom.
- Text and files you enter are processed locally, not uploaded
- No account, email address or sign-up is required
- Generated passwords and hashes are never stored or logged
- Third-party services, if any are added, are disclosed in the privacy policy
What you can do with these free online tools
OneStopWebTools brings together forty small, focused utilities that people otherwise hunt for across a dozen different websites. Each one does a single job well, runs in your browser and explains its method on the page. Here is what each group of tools is for.
SEO and digital marketing tools
If you publish web pages, the SEO tools help you check the details search engines read. The Meta Tag Analyzer reviews a page’s title, description and social tags, and the SERP Snippet Preview Tool shows roughly how a title and description may look in search results before you publish. For site setup, the Robots.txt Generator and XML Sitemap Builder produce correctly formatted files, while the UTM Link Builder keeps campaign tracking links consistent.
Text and writing tools
Writers, students and editors can use the Word Counter to check length limits, the Case Converter to fix capitalisation in one click and the Text Diff Checker to see exactly what changed between two drafts. Cleaning up lists and data is quicker with the Duplicate Line Remover and Find and Replace Tool.
Image and PDF tools
The Image Compressor reduces file size for faster web pages and email attachments, and the Image Resizer, Image Cropper and Image Format Converter prepare pictures for any upload form. For documents, the PDF Merger and Splitter combines or separates pages, and the PDF to Image Converter turns pages into pictures. Because these tools work inside your browser, your files are not uploaded to a server.
Calculators and converters
Everyday sums are covered by the Percentage Calculator, Discount Calculator and Profit Margin Calculator, which are handy for shoppers and small business owners alike. The Age Calculator and Date Difference Calculator count exact days, months and years, and the Unit Converter handles length, weight, temperature and more. Each calculator shows the formula it uses.
Developer tools
Developers can format and validate data with the JSON Formatter and Validator, encode values with the Base64 and URL encoders, test patterns in the Regex Tester and create checksums with the Hash Generator. The Password Generator uses your browser’s secure random number source, and nothing it creates is stored.
Questions people ask
Are the tools really free?
Yes. Every tool is free to use without an account, a trial period or usage limits beyond what your own device can handle. If the site displays advertising in future, it will be clearly labelled and will not block any tool.
Are my files uploaded anywhere?
No. Image, PDF and text tools read your files with your browser’s built-in file APIs and process them in memory on your device. You can confirm this by opening your browser’s developer tools and watching the Network tab while a tool runs.
Do the tools work on phones and tablets?
Yes. Every page adapts to small screens, and the tools use standard browser features available in current versions of Chrome, Safari, Firefox and Edge. Very large images and long PDFs may be slower on phones because they have less memory.
How accurate are the results?
Calculators use standard formulas, which each page shows, and text tools count exactly what you paste. Some results are estimates by nature — reading time, for example, depends on the reader. Each tool page has a “Limitations” section explaining where to take care.
Can I suggest a new tool or report a problem?
Please do. Use the contact page to describe the tool you need or the problem you found, including your browser and device if something did not work.
Find the right tool for the job
Browse all forty tools in one place, filter them by category or search for the task you have in mind.
Open the full directory