Hyperfocal Distance Calculator
Why hyperfocal distance matters
Hyperfocal distance is a practical focusing target when you want maximum depth of field (DoF)—common in landscapes, architecture, and street scenes where you want foreground detail and distant backgrounds to look acceptably sharp. If you focus your lens at the hyperfocal distance H, then everything from approximately H/2 to infinity will be within “acceptable sharpness” for your chosen aperture, focal length, and circle of confusion (CoC).
This calculator uses the standard thin-lens hyperfocal approximation. Results are only as good as the CoC you choose and how closely your real lens matches the simplified model (see Limitations & assumptions).
Formula (and units)
The classic hyperfocal distance equation is:
- H = hyperfocal distance (same distance unit as f and c)
- f = focal length (mm in this calculator)
- N = f-number (e.g., 8, 11, 16)
- c = circle of confusion (mm)
Unit note: Because f and c are in millimeters here, H is computed in millimeters. Convert to meters by dividing by 1000 (and to feet by dividing millimeters by 304.8).
Interpreting the result (near and far “acceptable sharpness”)
Once you have H, a widely used rule of thumb is:
- If you focus at H, the near limit of acceptable sharpness is about H/2.
- The far limit is infinity (in the same “acceptable” CoC sense).
In practice, photographers often focus slightly beyond the near subject (or use live view magnification) because real scenes, lenses, and print/viewing conditions vary.
Worked example
Setup: 24 mm lens, f/8, CoC = 0.03 mm (typical full-frame starting point).
- Compute the denominator: N·c = 8 × 0.03 = 0.24
- Square focal length: f2 = 242 = 576
- Divide: 576 / 0.24 = 2400 mm
- Add focal length: 2400 + 24 = 2424 mm
Result: H ≈ 2424 mm = 2.424 m (≈ 7.95 ft). If you focus at ~2.4 m, the near acceptable limit is roughly H/2 ≈ 1.2 m (≈ 4.0 ft), and the far limit is infinity.
Quick comparisons
The choice of CoC depends on sensor format and output assumptions. Smaller CoC values are stricter (they assume higher resolving demands), which increases the hyperfocal distance.
| Scenario | f (mm) | Aperture (N) | CoC (mm) | Hyperfocal H |
|---|---|---|---|---|
| Wide landscape (full-frame baseline) | 24 | 8 | 0.03 | ≈ 2.42 m |
| Standard view, more DoF | 35 | 11 | 0.03 | ≈ 3.75 m |
| Telephoto, stopped down | 50 | 16 | 0.03 | ≈ 5.26 m |
How to choose a circle of confusion (CoC)
CoC is not a physical constant; it’s a convention tied to how large you view/print the image and how sharp you expect it to look. Many calculators use “classic” defaults that work well for general purposes. As a starting point:
- Full-frame (35mm): ~0.03 mm
- APS-C: ~0.02 mm
- Micro Four Thirds: ~0.015 mm
If you plan large prints, heavy cropping, or very close viewing, use a smaller CoC (stricter). If your output is small (web-only) or viewing distance is large, a slightly larger CoC may be acceptable.
How to use this calculator
- Enter your focal length in millimeters.
- Enter your aperture (f-number).
- Enter a circle of confusion value appropriate for your camera/output.
- Calculate to get the hyperfocal distance. Optionally, treat H/2 as a quick estimate of the nearest distance that will look sharp when focused at H.
Limitations & assumptions
- “Acceptable sharpness” is subjective: Hyperfocal distance depends on CoC, which depends on viewing size, viewing distance, eyesight, and how much you crop.
- Thin-lens approximation: The formula assumes a simplified lens model. Real lenses (especially close-focus and complex designs) can deviate, and internal focusing can change the effective focal length.
- Focus distance reference: Distances are measured from the camera’s sensor/film plane (the “Φ” mark on many camera bodies), not from the front of the lens.
- Diffraction at small apertures: Stopping down increases DoF but can reduce overall sharpness due to diffraction (often noticeable at very small apertures, depending on sensor pixel pitch).
- Field curvature and decentering: Even if the hyperfocal math is correct, parts of the frame can be softer due to lens characteristics.
- Not a substitute for technique: Tripod stability, shutter speed, atmospheric haze, and subject motion can dominate perceived sharpness regardless of hyperfocal focusing.