CALLTO File - opening and understanding

Did your computer fail to open a CALLTO file? We explain what they are used for and recommend software that we know can open or otherwise handle your .CALLTO files.

What is a CALLTO file?

The CALLTO file extension indicates to your device which app can open the file. However, different programs may use the CALLTO file type for different types of data.

While we do not yet describe the CALLTO file format and its common uses, we do know which programs are known to open these files, as we receive dozens of suggestions from users like yourself every day about specific file types and which programs they use to open them.

We are continually working on adding more file type descriptions to the site, so if you have information about CALLTO files that you think will help others, please use the Update Info link below to submit it to us - we'd love to hear from you!

How to open CALLTO files

You will need a program compatible with the specific file you are trying to open, as different programs may use files with file extension CALLTO for different purposes.

While we have not verified the apps ourselves yet, our users have suggested 5 different CALLTO openers which you will find listed below.

Various viewers for this file format

These apps are known to open certain types of CALLTO files. Remember, different programs may use CALLTO files for different purposes, so you may need to try out a few of them to be able to open your specific file.

RingomaxRingomaxUser submitted
PTT JAPANPTT JAPANUser submitted
PTTJapanPlusPTTJapanPlusUser submitted
UcallWeconnUcallWeconnUser submitted
GlobalTalkGlobalTalkUser submitted

Try a universal file viewer

Try a universal file viewer like Free File Viewer. It can open over 200 different types of files - and most likely yours too. Download Free File Viewer here.

We have not yet verified any programs for Mac that work with this specific file format. If you know one, please use the 'Suggest a program' link below. Thanks!
We have not yet verified any web services that work with this specific file format. If you know one, please use the 'Suggest a program' link below. Thanks!