ToolRecipe
Stays on this device No watermark Works offline

What do you need to get done?

Drop a file here

or .

/

Open an app

Follow a recipe

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Use one tool

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Change file extensions

Change the extension of many files at once, for example .jpeg to .jpg or .txt to .md. Type the new extension once and every file gets it. Only the name changes: the contents are not converted, and nothing is uploaded.

How to change file extensions in bulk

  1. 1Drop your files in, or choose a folder
  2. 2Type the new extension, with or without a dot
  3. 3Check the table, then rename or download
  4. The same files, now ending in your new extension.

What happens to your files

  • Name only.The file contents are not touched, so this does not convert a format.
  • Dot or no dot."jpg" and ".jpg" give the same result.
  • Nothing is uploaded.Renaming runs in your browser, on your own device.

What you can do

  • Give every file the same new extension in one step, such as .jpeg to .jpg or .htm to .html.
  • Add an extension to files that have none.
  • See old and new names next to each other before anything changes.
  • Rename in place in Chrome or Edge on a computer, with an Undo button, or download renamed copies as a ZIP.

Good to know

  • Changing the extension does not change the file. A .png renamed to .jpg is still a PNG inside, and some programs will refuse to open it. To really convert, use an image converter.
  • Every file gets the extension you typed, whatever it had before. Drop only the files you want changed.
  • Leave the field empty and extensions are kept as they are.

Questions

Does changing the extension convert the file?

No. It only changes the name. The data inside stays in its old format, so use a converter if you need a different format.

Do I type the dot?

Either works. ".jpg" and "jpg" are treated the same.

Can I change the extension of a whole folder?

Yes, in Chrome or Edge on a computer: choose the folder, add subfolders if you like, and the files are renamed in place. Elsewhere you get a ZIP of renamed copies.

Related tools

How it works

Small tools that run in your browser.

Four steps

  1. Start with a file or a task

    Drop a file, search, or pick a task.

  2. The tool opens in a window

    Open as many as you like, side by side as tabs.

  3. Results collect on the right

    Drag a result into the next tool.

  4. Save when you're done

    Saved files go to your downloads.

Who uses what

Tool sets for common jobs.

Put a tool on your home screen

The icon opens that tool, like an app.

iPhone and iPad

  1. Open the tool in Safari.
  2. Tap Share (the square with the arrow).
  3. Choose “Add to Home Screen”, then Add.

Android

  1. Open the tool in Chrome.
  2. Tap the menu (⋮) at the top right.
  3. Choose “Add to Home screen” or “Install app”.

Computer

  1. Open the tool in Chrome or Edge.
  2. Click the install icon in the address bar.
  3. Choose Install.

Skills

Claude skills we use ourselves, one job each.