How to open CALLTO files
Did your computer fail to open a CALLTO file? We explain what CALLTO files are and recommend software that we know can open or convert 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!
Update info Upload example file
Various CALLTO openers
These apps are known to open certain types of CALLTO files. Since many different programs may use CALLTO files for different purposes, you may need to try a few of the apps to open your specific CALLTO file.
 | Ringomax | User submitted |
| PTT JAPAN | User submitted |
| PTTJapanPlus | User submitted |
| UcallWeconn | User submitted |
| GlobalTalk | User 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.