Choose the camera
Select full frame, Canon APS-C, standard APS-C, Micro Four Thirds or a smaller sensor.
See your depth of field before you shoot.
Adjust your camera, lens, aperture and distance to preview focus, background blur and framing in real time.
Build your shot
Start with a preset or adjust the five controls.
50mm · f/2.8 · Full Frame
Your subject is sharp with a softly separated background.
Near focus—
Far focus—
Total depth—
Field of view—
Camera math you can actually see.
Depth of field depends on several controls at once. FocalSim keeps them in one view, explains the result and gives you a setup you can share.
Shape the image
Move focal length, aperture and distance while the scene updates immediately.
Take the setup
Copy one link with every setting, near and far focus, total depth and field of view.
Plan portraits, landscapes and everything between.
What the preview means.
Is the simulation exact?
The focus distances use standard optical formulas. The visual scene is an educational approximation because real bokeh also depends on lens design, aperture blades and the background.
What changes depth of field?
Aperture, focal length, focus distance, sensor format and the chosen circle of confusion all affect the acceptable focus zone.
Why is Canon APS-C separate?
Most APS-C cameras use about a 1.5× crop factor, while Canon APS-C commonly uses 1.6×. FocalSim models them separately.
Does FocalSim upload my settings?
No. The calculator runs in your browser. Shared links contain only the settings visible in the tool.
Is it free?
Yes. The full simulator and focused calculators are free and require no account.