| Format | Extension | Number of Scales | Max Duration (sec) | Max Filesize (bytes) | Special Events |
| Nokia | .ott, .nokia, .noktxt | 4 | unlimited1 | 128 per SMS, up to 255 messages | n/a |
| RTTTL / RTX | .txt, .rtttl, .rtx | 4 | unlimited1 | unlimited2 | n/a |
| IMelody 1.0, 1.2 | .imy | 9 | unlimited1 | 128 per SMS | vibration, backlight, LED |
| EMS | .ems | 9 | unlimited1 | 140 per SMS, up to 256 messages | vibration, backlight, LED |
| eMelody | .emy | 2 (3 for extended EMS) | 30 | 128 | n/a |
| Sagem 1.0 | .sagem.10 | 4 | 30 | 128 | n/a |
| Motorola | .mot, .bin | 3 | 30 | 128 | n/a |
1 A ringtone may be looped, which makes its duration unlimited
2 RTTTL is generally not used for ringtone delivery, so it doesn't impose restrictions on the file size. After conversion from RTTTL, however, the resulting ringtone must adhere to the limitations of the target format and the device.