A LUT is a table of numbers. LUTsmith shows you the numbers before you commit a grade to them.

Inspection

• Dimension, size, domain and entry count
• Output range, plus counts of out-of-range and NaN/Inf entries
• Neutral-axis monotonicity: a reversing grey ramp is the usual cause of banding and solarised shadows
• Mean and maximum colour shift against identity
• Neutral-axis plot (R/G/B) and a hue × lightness map, input against output

Preview Any still image, or the built-in chart (hue sweep, ramps, 21-step scale, 24 reference patches). Wipe, after, before and ×4 difference views.

Operations

• Ordered stack of any number of LUTs, each with its own strength (linear blend toward identity)
• Bake the stack into a single 3D LUT at 17, 33 or 65 points, with optional 0–1 clamp
• Export any single LUT at its current strength, which also resamples 1D LUTs to 3D

Environment One offline HTML file. Chrome, Edge, Safari or Firefox. No network access, no account; files are processed locally.