User Guides - Sentinel-2 MSI - Level-1A Product - Sentinel Online
The Level-1A product is not released to users.
The L1A product is obtained by decompressing the Level-0 raw image data. A geometric model is developed, allowing any pixel in the image to be located. Each Level-1A product is a 25 km across track (AC) by 23 km along track (AL) granule. An average orbit will contain approximately 3,500 Level-1A granules. Level-1A pixel coordinates refer to the centre of each pixel.