Inputs
Results
Task/background ratio
--
Task/adjacent ratio
--
Maximum contrast ratio
--
Target exceeded
--
Contrast status
--
Calculation details
- Task/background ratio
- --
- Task/adjacent ratio
- --
- Maximum contrast ratio
- --
- Target exceeded
- --
- Contrast status
- --
Important notes
- Contrast ratio is a simple planning check; visual comfort still needs task and user context.
Formula
- \(\displaystyle C = E_{\mathrm{task}} / E_{\mathrm{surface}}\)
Compare task, background, and adjacent surface lux ratios against an entered target ratio.
Lighting Contrast Ratio Calculator is a planning aid. Keep the target source, product data, measurement method, and project assumptions with the result. Confirm compliance, installation, certification, and safety decisions with the responsible professional.