Depth of Field Calculator
Calculate depth of field, near focus limit, and far focus limit based on focal length, aperture, subject distance, and sensor size.
Depth of Field (DoF) describes the zone of a photograph where subjects appear acceptably sharp. Everything outside this zone blurs into what photographers call bokeh. Understanding DoF gives you creative control over which parts of your scene appear sharp and which dissolve into a smooth, out-of-focus background.
Core formulas:
Hyperfocal Distance (H) = (f² / (N × c)) + f
Near Focus Limit = (H × D) / (H + D − f)
Far Focus Limit = (H × D) / (H − D + f)
Depth of Field = Far Focus Limit − Near Focus Limit
Variable definitions:
- f — focal length in millimeters (e.g., 50mm, 85mm, 200mm)
- N — f-number (aperture setting: f/1.4, f/2.8, f/8, etc.)
- c — circle of confusion in millimeters (sensor-size dependent)
- D — focusing distance from the camera to your subject
- H — hyperfocal distance: the closest focus point at which infinity is still acceptably sharp
Circle of confusion by sensor size:
| Sensor | Circle of Confusion |
|---|---|
| Full Frame (35mm) | 0.030 mm |
| APS-C (Canon) | 0.019 mm |
| APS-C (Nikon/Sony) | 0.020 mm |
| Micro Four Thirds | 0.015 mm |
| 1-inch sensor | 0.011 mm |
Worked example: Camera: Full Frame. Lens: 85mm. Aperture: f/1.8. Subject distance: 8 ft (2.44 m). H = (85² / (1.8 × 0.030)) + 85 = (7,225 / 0.054) + 85 = 133,796 mm ≈ 438 ft At 8 ft distance with f/1.8, DoF = approximately 4–6 inches — razor thin.
Creative DoF control:
| To Get | Do This |
|---|---|
| Shallow DoF (blurry background) | Wide aperture (f/1.4–f/2.8), long focal length, close subject |
| Deep DoF (everything sharp) | Narrow aperture (f/8–f/16), short focal length, distant subject |
| Maximum DoF (landscape) | Focus at hyperfocal distance |
Real-world DoF ranges at f/2.8 with 85mm (full frame):
- Subject at 3 ft → DoF ≈ 0.4 inches
- Subject at 10 ft → DoF ≈ 4 inches
- Subject at 30 ft → DoF ≈ 39 inches
Portrait photographers typically shoot at f/1.4–f/2.8 to isolate subjects against blurred backgrounds. Landscape photographers use f/8–f/16 to keep foreground rocks and distant mountains equally sharp.