| Hardware and OS Realme C21Y |
| Operating system: | Android 10, Realme UI |
| Processor: | Octa-core (2x1.8 GHz Cortex-A75 & 6x1.8 GHz Cortex-A55) |
| Chipset: | Unisoc T610 (12 nm) |
| Internal memory: | 32GB 3GB RAM, 64GB 4GB RAM |
| External memory: | microSDXC (dedicated slot) |
| GPU: | Mali-G52 |
| Display Realme C21Y |
| Size: | 6.5 inches, 102.0 cm2 |
| Resolution: | 720 x 1600 pixels, 20:9 ratio |
| Type: | IPS LCD, 400 nits (typ) |
| Main Camera Realme C21Y |
| Camera: | 13 MP, f/2.2, 26mm (wide), 1/3.06", 1.12µm, PDAF
2 MP, f/2.4, (macro)
2 MP, f/2.4, (depth) |
| Features: | LED flash, HDR, panorama |
| Video: | 1080p@30fps |
| Selfie camera Realme C21Y |
| Camera: | 5 MP, f/2.2, (wide), 1/5.0", 1.12µm |
| Features: | HDR, panorama |
| Video: | 1080p@30fps |
| Connectivity Realme C21Y |
| 2G Network: | GSM 850 / 900 / 1800 / 1900 - SIM 1 & SIM 2 |
| 3G Network: | HSDPA 850 / 900 / 2100 |
| 4G Network: | 1, 3, 5, 8, 38, 40, 41 |
| Bluetooth: | 5.0, A2DP, LE |
| GPS: | Yes, with A-GPS, GLONASS, BDS |
| NFC: | No |
| Speed: | HSPA 42.2/5.76 Mbps, LTE |
| Technology: | GSM / HSPA / LTE |
| USB: | microUSB 2.0, USB On-The-Go |
| WLAN: | Wi-Fi 802.11 b/g/n, hotspot |
| Multimedia Realme C21Y |
| 3.5 mm Jack: | Yes |
| Loudspeaker: | Yes |
| Radio: | Unspecified |
| Battery Realme C21Y |
| Type: | Li-Po 5000 mAh, non-removable |
| Charging: | Reverse charging |
| Design Realme C21Y |
| Body build: | Glass front, plastic back, plastic frame |
| Colors: | Cross Black, Cross Blue |
| Dimensions: | 164.5 x 76 x 9.1 mm (6.48 x 2.99 x 0.36 in) |
| Weight: | 200 g (7.05 oz) |
| SIM: | Dual SIM (Nano-SIM, dual stand-by) |
| Features Realme C21Y |
| Sensors: | Fingerprint (rear-mounted), accelerometer, proximity, compass |
