Snell Law Calculator
At what angle does light refract into another medium? Enter the stated values to calculate this model.
Result for the values shown.
Calculations run in your browser.
What to enter
| Input | Meaning and units |
|---|---|
| Incident refractive index (1) | Enter incident refractive index in 1; use the same basis as the other measurements. |
| Transmitted refractive index (1) | Enter transmitted refractive index in 1; use the same basis as the other measurements. |
| Incident angle to normal (degree) | Enter incident angle to normal in degree; use the same basis as the other measurements. |
Understanding your result
Read Refraction angle (degree) in the units and model stated on this page. The formula ratio=n1*sin(angle*pi/180)/n2 · angleOut=asin(min(1,max(-1,ratio)))*180/pi defines the relationship; measurement accuracy and model applicability are separate from numerical precision.
Common mistakes
- Mixing input units or changing the physical meaning of a variable without changing the model.
Check your calculation
- Use the worked example as a known reference case, then change one input at a time and check the direction and units of the response.
Calculation checks, sources and review limits
At what angle does light refract into another medium?
At what angle does light refract into another medium? Enter the stated values to calculate this model.
Common uses
- At what angle does light refract into another medium
How it works
ratio=n1*sin(angle*pi/180)/n2; angleOut=asin(min(1,max(-1,ratio)))*180/pi
Worked example
Enter Incident refractive index: 1 1; Transmitted refractive index: 2 1; Incident angle to normal: 30 degree. Results: Refraction angle: 14.477512185929925 degree.