Quick Scoop: Demi-permanent hair color usually lasts about 4 to 6 weeks , or roughly 20 to 28 washes , before fading noticeably. It tends to last longer on healthier, less porous hair and shorter if you wash often or use heat, sun, or saltwater frequently.

Review-style take

Most sources agree it sits in the middle ground: longer-lasting than semi- permanent color, but not as permanent as permanent dye. A common “review” takeaway is that it fades gradually and looks soft as it goes, which many people like because it grows out more naturally.

What affects wear time

  • Hair porosity: more porous hair usually fades faster.
  • Wash frequency: more shampooing means quicker fading.
  • Sun, saltwater, and heat: these can speed up color loss.
  • Shade choice: lighter shades often fade sooner than deeper tones.

Forum-style consensus

A common stylist/forum view is that demi color is a good choice if you want a gentler, lower-commitment color refresh, but you should expect touch-ups more often than with permanent dye. One forum comment also noted that gray coverage can stain some strands yet still fade faster overall.

Bottom line

If you want a practical rule of thumb, plan on 4 to 6 weeks for demi- permanent hair color, with the exact result depending on your hair and care routine.

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