Optics Calculators & Tools

Apply the thin lens equation to find focal length, object, or image distance.

Use the mirror equation for concave and convex mirrors.

Calculate magnification from image and object distances or heights.

Calculate telescope and microscope angular resolution using Rayleigh criterion, Dawes’ limit, and Abbe diffraction limit.

Calculate circular, annular, and rectangular aperture areas, light-gathering ratios, and magnitude differences.

Calculate apparent distance, exit pupil, twilight factor, relative brightness, horizon distance, and field of view for binoculars.

Calculate Brewster’s angle, find refractive index from polarization angle, and analyze s/p-polarization reflectance.

Convert spectacle prescriptions to contact lens power using vertex distance compensation with clinical rounding.

Calculate diffraction angles, wavelengths, grating spacing, resolving power, angular dispersion, and screen positions using the grating equation.

Calculate refractive index, light speed in media, optical path length, wavelength in medium, relative index, and critical angle.

Convert between focal length and diopters, combine thin or separated lenses, calculate reading additions, and classify lens power.

Calculate horizon distance from height, curvature drop, dip angle, refraction correction, two-object visibility, and planetary horizons.

Calculate curvature drop, hidden height, bulge, line-of-sight distance, and refraction-adjusted curvature values.

Calculate focal length, refractive index, surface radii, optical power, and classify lens shapes using the Lens Maker's equation.

Calculate laser beam divergence, Gaussian beam propagation, Rayleigh range, M² beam quality, and spot size at distance.

Calculate focused spot size, beam waist, power density, beam area, and Rayleigh range for laser applications.

Calculate expansion ratio, output diameter, divergence reduction, and design Galilean or Keplerian beam expanders.

Calculate laser brightness (radiance), beam parameter product, irradiance, compare lasers, and M²-corrected brightness.

Convert between frequency linewidth and wavelength bandwidth, calculate coherence time, coherence length, Q factor, and spectral purity.

Convert between lumens, lux, candela, and footcandles. Calculate illumination at distance, beam angle effects, and light output requirements.

Convert between lux (SI) and foot-candles (imperial) for lighting design and building code compliance.

Calculate polarized light intensity using Malus's law. Find transmitted intensity, polarizer angle, or transmission coefficient.

Calculate image distance, object distance, focal length, and magnification for concave and convex mirrors.

Convert between optical density (OD), transmission %, and attenuation factor for filters, laser safety, and spectroscopy.

Calculate radar line-of-sight distance with Earth curvature and atmospheric refraction k-factor.

Calculate refraction angle, incident angle, refractive index, and critical angle using Snell's law with TIR detection.

Calculate light speed in any medium, travel time, and distances. Supports astronomical units (AU, ly, pc) and refractive index.

Calculate true field of view from AFOV or field stop. Plan which eyepiece frames celestial objects.

Calculate magnification, exit pupil, and useful magnification range for any telescope and eyepiece setup.

Calculate quarter-wave AR coating thickness, ideal coating index, and residual reflectance for optical coatings.

Solve the thin lens equation for image distance, focal length, magnification, and image characterization.