Are these data & spreadsheets tools really free?

Yes. Every tool on this page is free, with no account, no watermark and no usage limit. They are funded by our development work, not by charging for conversions.

Do my files get uploaded?

No. Each tool converts your file with JavaScript inside your own browser, so the file never travels to a server. That also means the only size limit is your device's memory.

Can I use these on my phone?

Yes. The tools work on Android and iOS as well as desktop, and they keep working offline once the page has loaded.

Something went wrong. Why?

The usual causes are a very large file on a low-memory phone, or an unusual variant of the format. Converters that re-encode video are the slowest, because they do real work rather than just repackaging.

Free CSV, JSON & Excel Tools

Move data between CSV, JSON, XML and Excel without pasting it into a web form. Everything is parsed in the browser.

Data & Spreadsheets — 7 tools

CSV, JSON, XML & Excel

CSV to Excel Convert CSV data into an Excel workbook. Excel to CSV Convert Excel sheets to CSV. JSON to CSV Convert JSON data to CSV. CSV to JSON Convert CSV into JSON data. XML to JSON Convert XML to JSON. JSON to XML Convert JSON to XML. Excel to Google Sheets Prepare an Excel file for a perfect Google Sheets import.

How to pick the right data & spreadsheets tool

Every tool on this page does one job well, and the name says which job. If you are converting a file once, just take the one that matches your format pair. If you are converting dozens on a schedule, a dedicated tool in a browser is the wrong shape — that is a workflow problem, and it is worth automating properly.

Two things are worth checking before you start. First, whether your file needs a full re-encode (slower) or just a repackage (instant) — a converter that says "re-encodes" will take noticeably longer. Second, whether the output format supports what you need: MP3 for sharing, WAV for editing, JPG for photos, PNG for anything with text or transparency.

Why these tools run in your browser

Free online converters usually pay for themselves with your data. The file is uploaded, written to a temporary folder, and deleted "after a while" — which is fine for a holiday photo and a bad idea for a signed contract, an unreleased design, or anything belonging to a client.

Every tool here runs with JavaScript on your own device instead. Nothing is uploaded, so there is no file-size limit, no queue and nothing to delete. It also means the tools keep working with no connection once loaded, which is useful when the Wi-Fi is the actual problem.

Common questions

Are these data & spreadsheets tools really free?: Yes. Every tool on this page is free, with no account, no watermark and no usage limit. They are funded by our development work, not by charging for conversions.
Do my files get uploaded?: No. Each tool converts your file with JavaScript inside your own browser, so the file never travels to a server. That also means the only size limit is your device's memory.
Can I use these on my phone?: Yes. The tools work on Android and iOS as well as desktop, and they keep working offline once the page has loaded.
Something went wrong. Why?: The usual causes are a very large file on a low-memory phone, or an unusual variant of the format. Converters that re-encode video are the slowest, because they do real work rather than just repackaging.

Need this done at scale?

These tools are built for one file at a time. If you need the same conversion run automatically over hundreds of files, or wired into an app you already have, that is a build job — and we do those.

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