Interactive Camera Exposure Calculator
Enter your current exposure settings, choose what to solve for, then enter the target values. Shutter speed accepts formats like 1/125 or 0.008.
Current (Base) Exposure
Target Settings
What this camera exposure calculator does
This tool helps you keep exposure consistent when you change one or two parts of the exposure triangle: aperture, shutter speed, and ISO. In practical terms, that means you can quickly answer questions like: “If I open up from f/4 to f/2.8, what shutter speed should I use?” or “If I lower ISO for cleaner images, how much longer should my shutter be?”
The calculator is built for real-world shooting. You can enter shutter speeds as fractions (like 1/250) or decimals (like 0.004), and it returns a result you can use immediately in-camera.
Exposure triangle basics
Aperture (f-number)
Aperture controls how wide the lens opens. Lower f-numbers (f/1.8, f/2.8) let in more light and create shallower depth of field. Higher f-numbers (f/8, f/11) let in less light and increase depth of field.
Shutter speed
Shutter speed controls how long light reaches the sensor. Faster speeds (1/1000) freeze action. Slower speeds (1/30, 1 second) capture motion blur and require steadier support.
ISO
ISO controls sensor amplification. Higher ISO brightens the image but can add noise. Lower ISO keeps cleaner files but needs more light from aperture and/or shutter.
How to use the calculator
- Enter your known base exposure settings (aperture, shutter speed, ISO).
- Select what you want to solve for: shutter speed, aperture, or ISO.
- Enter the other target values you already know.
- Click Calculate Exposure.
The output also includes stop change information, so you can see how dramatic your change is.
Example scenarios
Portrait in low light
Suppose your base exposure is f/4, 1/125, ISO 100. You want stronger background blur, so you switch to f/2.8. The calculator will show you the equivalent shutter speed to maintain brightness. That helps you preserve exposure while changing depth of field intentionally.
Landscape with tripod
If your base is f/5.6, 1/60, ISO 400 and you want cleaner image quality at ISO 100, you can solve for shutter speed. The result will be a longer exposure, which is usually fine on a tripod.
Common exposure mistakes this helps prevent
- Changing aperture for artistic reasons but forgetting to compensate shutter speed.
- Dropping ISO for quality, then accidentally underexposing the frame.
- Using inconsistent exposure settings between similar shots.
- Guessing equivalent values instead of calculating accurate compensation.
Quick reference: one-stop changes
- Shutter: 1/1000 → 1/500 → 1/250 → 1/125 → 1/60 (each step doubles/halves light)
- Aperture: f/1.4 → f/2 → f/2.8 → f/4 → f/5.6 → f/8 (each step halves/doubles light)
- ISO: 100 → 200 → 400 → 800 → 1600 (each step doubles/halves brightness sensitivity)
Final thoughts
Mastering exposure is less about memorizing numbers and more about controlling tradeoffs quickly. Use this camera exposure calculator to move faster in the field, make cleaner decisions, and shoot with confidence.