An image converter is a kind of file converter that converts one image file format (like a JPG, BMP, TIF, etc.) into another. If you're unable to use a photo, graphic, or any kind of image file the way you'd like because the format isn't supported, image converter software can help.
Important: Every image converter program listed below is freeware. I have not included trialware or shareware image converters.
Here's a list of the best completely free image converter software programs and online services:
XnView is the Swiss Army knife of image converters. With XnView, you can convert any of around 400 image formats to your choice of about 50 others. If you have a rare image format that you can't open, XnView can probably convert it.
XnView also supports batch conversion and several other advanced options.
Input Formats: BMP, EMF, GIF, ICO, JPG, PCX, PDF, PNG, PSD, RAW, TIF, and many more
Output Formats: BMP, EMF, GIF, ICO, JPG, PCX, PDF, PNG, PSD, RAW, TIF, and many more
You can see the complete list of supported formats here: XnView Formats. The publisher of XnView also has a free command line based, dedicated image converter called NConvert but XnView is much easier to use.
The CoolUtils Online Image Converter is just that - an image converter that exists completely online, no download required.
Unlike other online image converters, the CoolUtils service does the image converting for you in real time - no waiting on an email link.
Input Formats: BMP, GIF, ICO, JPEG, PNG, and TIFF
Output Formats: BMP, GIF, ICO, JPEG, PNG, and TIFF
I'm assuming there's a file size limit on the original file you upload but I couldn't confirm one. I uploaded and converted a 17MB TIFF file to a JPEG without problem.
YouConvertIt is another online image converter service that will convert most common graphics formats.
Just upload the original image, choose the desired output, and then wait for an email with a link to your image in the new format.
Input Formats: BMP, EMF, GIF, ICO, ICON, JPEG, JPG, PNG, TIFF, and WMF
Output Formats: BMP, EMF, GIF, ICO, ICON, JPEG, JPG, PNG, TIFF, and WMF
Zamzar is yet another online image converter service that supports most common photo and graphic formats and even a few CAD formats.
Input Formats: BMP, DWG, DXF, GIF, JPG, PCX, PNG, TGA, TIFF, and WBMP
Output Formats: BMP, GIF, ICO, JPG, PDF, PS, PCX, PNG, TGA, TIFF, and WBMP
I've repeatedly tested Zamzar and have found the conversion time slower than most other online image converter services. Try an actual software program or one of the other online image converter services before Zamzar.