Nokia N81
| General | Form Factor | Slider |
| Network | GSM 850 / 900 / 1800 / 1900 / UMTS 2100 | |
| Size | 102 x 50 x 17.9 mm, 86 cc | |
| Weight | 140 g | |
| Battery Type | Li-Po 1050 mAh | |
| Talk Time | 4 h | |
| Standby Time | 410 h | |
| Display | Display Type | TFT |
| Display Size | 2.4 inches (240 x 320 pixels) | |
| Display Colors | 16 | |
| External display | No | |
| Memory | Internal Memory | 12 MB |
| Card Slot | microSD, 2 GB card included | |
| Camera | Type | 2 megapixel (1600 x 1200) |
| Zoom | Yes | |
| Flash | Yes | |
| Video | Yes, QVGA at 15fps | |
| Secondary Camera | Yes, CIF camera | |
| Messaging | SMS | Yes |
| MMS | Yes | |
| EMS | No | |
| IM | Yes | |
| Yes | ||
| Connectivity | GPRS | Yes |
| EDGE | Yes | |
| 3G | Yes | |
| Wi-Fi | Yes | |
| Infrared | No | |
| Bluetooth | Yes, v2.0 with A2DP | |
| USB | Yes, microUSB | |
| Features | OS | Symbian OS 9.2, S60 rel. 3.1 |
| Browser | Yes | |
| Games | Yes | |
| Other | 96 MB SDRAM memory ARM 11 369 MHz processor Touch-sensitive Navi wheel Java MIDP 2.0 MP3/AAC/MPEG4 player Stereo FM Radio Push to talk PIM including calendar, to-do list 3.5 mm audio output jack Built-in handsfree |