For most people, exfoliating one to three times a week is plenty. The right number depends on your skin type, the exfoliant you use, and the rest of your routine. Daily is rarely necessary and is the fastest way to tip a healthy barrier into irritation.
By skin type
Oilier, resilient skin can usually handle the higher end, two to three times a week. Normal skin sits comfortably around two. Dry or sensitive skin often does best at once a week, sometimes less. These are starting points, not rules: the goal is the lowest frequency that keeps your skin smooth, because that is the frequency your barrier can sustain.
It depends on the exfoliant
A gentle lactic acid is not the same as a strong glycolic peel, and a leave-on salicylic is not the same as a physical scrub. Stronger and leave-on formulas need less frequency. If you also use a retinoid, count that toward your skin's total weekly load and exfoliate less, not more.
Exfoliation is a small, occasional nudge, not a daily habit. The skin that looks best is usually the skin that is exfoliated least often enough to stay smooth.
Signs you have gone too far
Over-exfoliation looks like tightness that does not ease, stinging from products you used to tolerate, new redness, a shiny or waxy look, and small flakes. If you see these, stop all acids and scrubs, simplify to a gentle cleanser and a barrier moisturiser, and let the skin recover for two to four weeks before reintroducing anything.
How to set your frequency
Start lower than you think you need, once a week, and only increase if your skin stays comfortable. Read the response over a few weeks rather than a few days. Smoother, more even skin means the frequency is right; any of the warning signs above means step it back.