For quick calibration without special hardware: open an online screen test with color patterns and adjust your monitor's brightness, contrast, and color temperature. Set brightness so white is bright but not blinding, and you can still distinguish between near-white shades in a gradient. Set contrast so you can see detail in both dark shadows and bright highlights. Adjust color temperature to match your work environment (6500K/D65 is the standard for most work). On Windows: search for "Calibrate display color" in Settings to use the built-in calibration wizard. On Mac: System Settings > Displays > Color profile > Customize to access the display calibrator assistant. For professional color work (photography, design), use a hardware calibrator like a Datacolor SpyderX or X-Rite i1 — software calibration is limited because it can't measure what your monitor actually outputs. After calibrating, avoid blue-light filters during color-critical work.
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