Science calculator
Lens Equation Calculator
Calculate image distance and magnification for thin lenses.
About the lens equation calculator
The lens equation calculator computes image distance and magnification for thin lenses.
How to use this calculator
- 1
Enter focal length
Enter the lens focal length in cm.
- 2
Enter object distance
Enter the object distance in cm.
- 3
View results
See image distance and magnification.
How the calculation works
1/f = 1/d₀ + 1/dᵢ. M = −dᵢ/d₀. Positive f = converging.
Example: f=10cm, d₀=30cm: dᵢ=15cm, M=−0.5 (inverted).
Understanding scientific constants
Key constants used: g = 9.81 m/s² (Earth gravity), c = 299,792,458 m/s (speed of light), G = 6.674×10⁻¹¹ N·m²/kg² (gravitational constant), h = 6.626×10⁻³⁴ J·s (Planck's constant), R = 8.314 J/(mol·K) (ideal gas constant). Results assume ideal conditions — real-world measurements may vary.
Ideal vs. real-world conditions
Most physics calculators assume ideal conditions: no air resistance, perfect vacuums, uniform gravity. Real-world results will differ due to friction, air resistance, temperature variations, and measurement uncertainty. Use these tools for learning and estimation, not precision engineering.
Important limitations
This tool provides a mathematical estimate based only on the values entered. It does not account for regulations, taxes, lender fees, market conditions, or individual circumstances. Results are for planning purposes only — consult a qualified professional for regulated, medical, financial, or construction decisions.
Frequently asked questions about lens equation calculator
How accurate is the lens equation calculator?+
The calculation follows the displayed formula and retains full numeric precision before formatting the result.
Can I use the result professionally?+
Use it as a planning estimate. Confirm regulated, medical, financial, or construction decisions with a qualified professional.