Bragg Law Calculator
Solve Bragg angle, lattice-plane spacing or wavelength for an entered diffraction order, with possible-order checks.
YOUR CALCULATION
Result
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Calculation steps
Work through one step at a time or reveal the complete calculation. The steps use your current inputs.
How to calculate
Convert wavelength and spacing to SI, keep the diffraction order as a positive integer and rearrange nλ=2d sinθ for the selected unknown.
nλ=2d sinθ
Worked example
For n=1, λ=0.15406 nm and d=0.2 nm, sinθ=0.38515, so θ≈22.653° and the scattering angle 2θ≈45.306°.
Assumptions and input details
Scalar ideal Bragg condition for elastic diffraction from parallel lattice planes. θ is the angle between the beam and planes; many instruments display 2θ. Inputs do not identify a material, Miller indices, intensity, structure factor, refraction, peak width or instrument calibration.
References: NIST: Bragg equation
Unit definitions
Unit selection is independent of language. Each selector contains only units for its physical quantity. Calculations use defined base units internally.
Choose from 23 length definitions, including explicitly labelled regional measures. Area conversions square the length factor; geometric volumes cube it.
Regional measures are not interchangeable merely because their names look similar. This is a documented selection, not a claim to include every historical unit.
NIST measurement tables · Japanese traditional units · Mainland China and Hong Kong unit distinctions
Using this calculator
Can I enter my own problem?
Yes. Replace the example values with your own inputs. The result, calculation steps, tables and applicable diagrams update from those inputs. Blank or invalid values clear the result; example values are never silently substituted for missing inputs.
Are the results exact?
Results use floating-point arithmetic and displayed rounding. Read the formula, assumptions and any stated data precision before interpreting the result.
Is my input uploaded?
The calculation runs in your browser. No account, file upload or external AI service is required. Inputs are not saved between page reloads.
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