| Hardware and OS | Nokia C21 | |
| Operating system | Android 11 (Go edition) | |
| Processor | Octa-core (4x1.6 GHz Cortex-A55 & 4x1.2 GHz Cortex-A55) | |
| Chipset | Unisoc SC9863A (28nm) | |
| GPU | IMG8322 | |
| Internal memory | 32GB 2GB RAM, 32GB 3GB RAM, 64GB 3GB RAM | |
| External memory | microSDXC (dedicated slot) | |
| Display | Nokia C21 | other phones |
| Type | IPS LCD | |
| Size | 6.52 inches, 102.6 cm2(~77.5% screen-to-body ratio) | |
| Resolution | 720 x 1600 pixels, 20:9 ratio | |
| Colors | Dark Blue, Warm Gray | |
| Design | Nokia C21 | other phones |
| Body build | Glass front, aluminum frame, plastic back | |
| SIM | Single SIM (Nano-SIM) or Dual SIM (Nano-SIM, dual stand-by) | |
| Dimensions | 169.9 x 77.9 x 8.8 mm (6.69 x 3.07 x 0.35 in) | |
| Weight | 195 g (6.88 oz) | |
| Connectivity | Nokia C21 | other phones |
| 2G Network | GSM 850 / 900 / 1800 / 1900 - SIM 1 & SIM 2 (dual-SIM model only) | |
| 3G Network | HSDPA 850 / 900 / 2100 - International | |
| 4G Network | LTE | |
| WLAN | Wi-Fi 802.11 b/g/n, hotspot | |
| Bluetooth | 4.2, A2DP | |
| GPS | Yes, with A-GPS | |
| NFC | No | |
| USB | microUSB 2.0 | |
| CDMA | HSDPA 850 / 900 / 1700(AWS) / 1900 / 2100 - LATAM, Brazil | |
| Speed | HSPA 42.2/5.76 Mbps, LTE Cat4 150/50 Mbps | |
| Technology | GSM / HSPA / LTE | |
| Main Camera | Nokia C21 | other phones |
| Camera | 8 MP | |
| Features | LED flash, HDR | |
| Video | 720p@30fps | |
| Selfie camera | Nokia C21 | other phones |
| Camera | 5 MP | |
| Features | LED flash | |
| Video | 720p | |
| Multimedia | Nokia C21 | other phones |
| Radio | FM radio | |
| 3.5 mm Jack | Yes | |
| Loudspeaker | Yes | |
| Features | Nokia C21 | other phones |
| Sensors | Fingerprint (rear-mounted), accelerometer, proximity | |
| Battery | Nokia C21 | other phones |
| Type | Li-Ion 3000 mAh, removable | |
