Glossary
Sensor size
The physical area of a camera's image sensor. Larger sensors gather more light, deliver less noise, shallower depth of field, and better low-light performance. The single biggest determinant of image quality.
Sensor size dwarfs almost every other camera spec for image quality.
Common sizes (smallest to largest)
- 1/2.5" – 1/1.3" — smartphone sensors. Area: 24–58 mm².
- 1" — premium compacts, top phones (Xiaomi 14 Ultra). 116 mm².
- Four Thirds — Panasonic, OM System. 225 mm².
- APS-C — Sony, Fujifilm, Canon mid-tier. 332–370 mm².
- Full Frame (35 mm) — 864 mm².
- Medium Format — Fujifilm GFX, Hasselblad. 1,452 mm².
Practical effect
Each step up roughly doubles light capture. A full-frame at ISO 6400 looks like an APS-C at ISO 3200 or a Four Thirds at ISO 1600.
Depth of field
Larger sensors give shallower DoF at equivalent framing — the "creamy bokeh" look. Phones simulate this computationally; results vary.
Where this matters
Categories that use sensor size
See it compared
Sensor size on real comparisons
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