Free Online Tools for Images, Files and Developers

Convert image formats, combine files into PDFs, format JSON, validate XML and generate structured data from one place.
Choose a tool below and get straight to the task.

Latest guides

Practical, step-by-step help for getting more out of every tool.

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  • XML Toolkit

    How to Validate XML Against an XSD Schema (and Fix the Errors)

    A schema says exactly what an XML file must look like. Here’s how to check a file against one, and a plain-language guide to the error messages, which are always in English, with the fix for each.

    30 October 2026 · 7 min read
  • File Comparison

    How to Compare Two Excel or CSV Files and Find the Differences

    Two versions of a price list, a guest list or an export, and you need to know what changed. Here’s how to compare them row by row in minutes, and the one step that makes the result clean instead of noisy.

    30 October 2026 · 6 min read
  • JSON Toolkit

    JSON vs YAML: Differences, When to Use Each, and How to Convert

    JSON and YAML can describe exactly the same data, but they feel very different to work with. Here’s how they compare, when to pick each, and the YAML traps that quietly turn “NO” into false.

    30 October 2026 · 6 min read
  • Convert Images Online

    How to Convert PNG to WebP (and When You Shouldn’t)

    PNG files are often far bigger than they need to be on a website. Here’s how to turn them into WebP, which quality setting to use, and the few cases where PNG is still the better choice.

    30 October 2026 · 5 min read
  • QR Code Generator

    How to Make a vCard QR Code for Your Business Card

    A vCard QR code on your business card saves people typing your name, number and email. Here’s what to put in it, why less is often more, and how big to print it so it scans every time.

    30 October 2026 · 6 min read
  • XML Toolkit

    How to Convert CSV to XML (Excel and Google Sheets Too)

    Many systems still import XML, while your data lives in a spreadsheet. Here’s how to turn each row into a clean XML record, choose good element names, and avoid the CSV problems that break conversions.

    30 October 2026 · 6 min read
  • XML Toolkit

    How to Use XPath to Find Data in XML (with Examples)

    XPath is a short way to point at exactly the data you need inside an XML file. Here are the expressions you’ll actually use, each with its result, and the two mistakes that trip up almost everyone.

    30 October 2026 · 7 min read
  • XML Toolkit

    How to Convert XML to JSON: Attributes, Arrays and Types Explained

    XML and JSON describe the same data in different ways, so converting between them involves a few choices. Here’s what happens to attributes, repeated elements and numbers, and how to get JSON your code can rely on.

    29 October 2026 · 6 min read

Frequently asked questions

Are the tools really free?

Yes. Every tool is free to use with no sign-up and no watermark. Each tool has a daily allowance, shown above it, that resets at midnight UTC.

Do I need to create an account?

No. Open a tool and start working. There is nothing to install and no account to create.

Are my files uploaded to your server?

Almost never. Images, PDFs, QR codes, JSON, XML and schema markup are made inside your browser, so your files stay on your device. Only File Comparison sends the two texts to our server to work out the differences, and they are not saved.

Do the tools work on my phone?

Yes. Every tool works in the browser on phones, tablets and computers, on Windows, macOS, Linux, Android and iPhone.

Which languages is DeviTools available in?

English, Spanish, German and French. Switch with the language menu at the bottom of every page.

Will you add more tools?

Yes. New tools are added regularly. If there is a tool you would like to see, tell us through the Contact page.