Hyperfocal Distance Calculator
Calculate the hyperfocal distance — the closest focusing distance at which objects at infinity are acceptably sharp. Knowing this helps maximize depth of field in landscape and street photography.
Formula
Full formula:
H = f² / (N × c) + f
Simplified (common approximation, valid when f ≪ H):
H ≈ f² / (N × c)
Where:
- H = Hyperfocal distance (mm)
- f = Focal length of the lens (mm)
- N = Aperture f-number (dimensionless)
- c = Circle of confusion (mm) — the maximum acceptable blur spot diameter on the sensor
When the lens is focused at the hyperfocal distance H, everything from H/2 to infinity is acceptably sharp.
Assumptions & References
- The circle of confusion (CoC) is derived from the sensor size and an assumed standard viewing distance/print size. Common values: 0.029 mm (full frame), 0.019–0.020 mm (APS-C), 0.015 mm (Micro Four Thirds).
- The simplified formula H ≈ f²/(Nc) is accurate to within 0.1% for typical photographic focal lengths and apertures, since f is much smaller than H.
- This calculator uses the full formula H = f²/(Nc) + f for maximum accuracy.
- Depth of field calculations assume a thin lens model and paraxial (small-angle) optics.
- Reference: Sidney F. Ray, Applied Photographic Optics, 3rd ed., Focal Press, 2002.
- Reference: Leslie Stroebel, View Camera Technique, 7th ed., Focal Press, 1999.
- The hyperfocal distance concept is also described in ISO 12233 and various photographic standards bodies.