Flat iron temperature chart by hair type
Where to start on the dial for fine hair, wigs, Type 3 curls and Type 4 coily hair — and when to go higher.
Starting temperatures
| Hair | Start at | Don't go above | Notes |
|---|---|---|---|
| Fine, thin or color-treated | 300°F | 340°F | Fragile or processed hair needs the least heat. Start at the bottom and stay there if one slow glide leaves it smooth. |
| 100% human-hair wig, bundles & leave-out | 320°F | 340°F | Human hair only — never synthetic fibers. Test a hidden section first; wig hair does not grow back. |
| Type 3 curls (3A–3C) | 375°F | 410°F | Curls need enough heat to release the pattern in one pass; the right number depends on density more than curl type. |
| Type 4 coily (4A–4C) | 410°F | 450°F | Dense, coily hair usually needs the upper range — but only with clean, fully dry hair, a heat protectant and thin sections. |
Choosing an iron too? Compare the 2" Wide, 1" Classic and 0.3" Mini, or take the 30-second quiz for a width and a starting temperature.
The rule that matters more than the number
Start at the low end of your range. If a section is smooth after one slow glide, stay there. Go up one step only when it isn't. More heat is not a faster silk press — going over the same section again and again does more damage than one pass at the right temperature.
Before you turn it up
- Hair must be clean and completely dry. Never press wet or damp hair.
- Use a heat protectant every time.
- Work in thin sections — about 1.5" wide and 0.5" thick, as the manual recommends. Thick sections need more heat to get through.
Color-treated, relaxed or damaged hair
Processed hair is weaker. Stay in the fine-hair range even if your curl type is coarse, and stop if you see smoke, smell burning or hear sizzling — that means the hair is wet or the heat is too high.
These are starting points, not medical advice. Check the instruction manual for your iron.
2" Titanium Wide
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