Field of View

Focal lengths / APS-C (Canon)

21mm on APS-C (Canon)

Frames like 33.6mm on full frame: 55.9° across, 39.1° top to bottom.

Reference photo: Forest
A 33.6mm eq.
The scene as framed by 21mm APS-C (Canon)
A What 21mm APS-C (Canon) sees
A 21mm on APS-C (Canon)
Focal length21mm
Full-frame equivalent33.6mm
Horizontal55.9°
Vertical39.1°
Diagonal65.1°
SensorAPS-C (Canon) 22.3 × 14.9 mm
Crop factor×1.6
Aspect ratio3:2

Compare it with another setup →

Same framing on other formats

The focal length that matches 33.6mm full-frame equivalent on each sensor size (crop-factor convention, diagonal).

SensorFocal lengthClosest page
Medium format42.5mm45mm on Medium format
Full frame33.6mm35mm on Full frame
APS-C22.4mm23mm on APS-C
Micro Four Thirds16.8mm17mm on Micro Four Thirds
1-inch12.4mm—

Primes at 21mm for APS-C (Canon) (1)

LensFocalApertureMountYear
Samyang 21mm f/1.4 ED AS UMC CS (EF-M)21mmf/1.4Canon EF-M2015
Zooms that reach 21mm (15)
LensFocalApertureMountYear
Canon EF-M 11-22mm f/4-5.6 IS STM11–22mmf/4–5.6Canon EF-M2013
Canon EF-M 15-45mm f/3.5-6.3 IS STM15–45mmf/3.5–6.3Canon EF-M2015
Canon EF-M 18-150mm f/3.5-6.3 IS STM18–150mmf/3.5–6.3Canon EF-M2016
Canon EF-M 18-55mm f/3.5-5.6 IS STM18–55mmf/3.5–5.6Canon EF-M2012
Canon RF-S 14-30mm f/4-6.3 IS STM PZ14–30mmf/4–6.3Canon RF2025
Canon RF-S 18-45mm f/4.5-6.3 IS STM18–45mmf/4.5–6.3Canon RF2022
Canon RF-S 18-150mm f/3.5-6.3 IS STM18–150mmf/3.5–6.3Canon RF2022
Laowa 12-24mm f/5.6 Zoom Shift CF (EF-M)12–24mmf/5.6Canon EF-M2024
Laowa 12-24mm f/5.6 Zoom Shift CF (RF)12–24mmf/5.6Canon RF2024
Sigma 16-300mm f/3.5-6.7 DC OS | C (RF)16–300mmf/3.5–6.7Canon RF2025
Sigma 17-40mm f/1.8 DC | A (RF)17–40mmf/1.8Canon RF2025
Sigma 18-50mm f/2.8 DC DN | C (RF)18–50mmf/2.8Canon RF2024
Tamron 16-50mm f/2.8 A (RF)16–50mmf/2.8Canon RF2026
Tamron 17-70mm f/2.8 Di III-A VC RXD (RF)17–70mmf/2.8Canon RF2026
Tamron 18-300mm f/3.5-6.3 Di III-A VC VXD (RF)18–300mmf/3.5–6.3Canon RF2025