The Samsung Galaxy A21s features a 6.5-inch HD+ Infinity-O display with 720×1600 pixels resolution. The phone is powered by 2GHz octa-core processor. It comes in three variants - 3GB RAM and 32GB of internal storage, 4GB RAM and 64GB of internal storage and 6GB RAM and 64GB of internal storage. There is also a dedicated microSD card slot for up to 512GB for storage expansion.
For the camera, the Samsung Galaxy A21s has a quad-camera setup of a 48-megapixel sensor primary sensor with f/2.0 aperture, an 8-megapixel ultra-wide sensor with f/2.2 aperture, a 2-megapixel macro camera with f/2.4 aperture, and a 2-megapixel depth sensor with f/2.4 aperture. On the front, there is a 13-megapixel selfie shooter with f/2.2 aperture placed in the hole-punch located in the top left corner of the screen.
The Samsung Galaxy A21s is backed up by a 5,000mAh battery with 15W fast charging support. On the software front, the Samsung Galaxy A21s runs Android 10-based One UI 2.0 out of the box.