There is no one magic number. Your hair is unique. Your desired outcome is unique. So experiment. Try 20 minutes one week, 35 the next. Take notes. Laugh at the results.
Here’s a quirky secret: time isn’t the only ruler. The temperature of your bathroom matters. A steamy shower speeds things up. A cold day slows it down. You’re a chemist in your own home.
So go wild. Set a timer. Watch a TikTok. Sniff the dye (don’t—it smells weird). Remember: semi-permanent is forgiving. It’s the friend who lets you borrow their sweater and doesn’t care if you spill coffee on it.
At the end of the day, the best time is the one that makes you grin when you look in the mirror. Even if that time is only 12 minutes. Even if you look slightly like a cartoon character. That’s the whole point.
