Quick answer: for blue hair at home, use a semi-permanent blue dye: ready to use, no developer, fading gradually over several washes with no regrowth line. Blue shows truest on very pale, cool blonde hair. On yellow or golden blonde it can look slightly green, because blue and yellow make green, and on dark hair it gives a blue sheen in the light rather than bright blue. Insight's Enhancing Color Pigments in Blue Velvet are vegan and cruelty-free.
Blue is a bold, cool fashion colour that works as all-over colour, blue tips, peekaboo panels or a deep blue-black sheen. Here's how to get the shade you actually want.
What colour does my hair need to be for blue?
Semi-permanent colour adds pigment but doesn't lighten, and blue is the shade most affected by what's underneath:
- Platinum or very pale, cool blonde: the truest, brightest blue.
- Yellow or golden blonde: blue mixes with the yellow and can look teal or green. Toning the yellow out first gives a cleaner blue; see how to get rid of brassy hair.
- Light to mid brown: a blue tint, mainly visible in daylight.
- Dark brown or black: a deep blue-black sheen in the light, a popular subtle look. For bright blue on dark hair, you'd need lightening in the salon first.
Why does blue hair fade to green?
If your hair still has some yellow in it, the yellow shows through more as the blue fades, and blue plus yellow reads as green or teal. It's colour theory, not a faulty product. To avoid it, start on the palest, coolest base you can, and top up the blue before it fades too far.
Blue hair ideas
- All-over blue on pre-lightened hair for maximum impact.
- Blue tips or ends, easy to cut off or grow out.
- Peekaboo blue: a lightened panel underneath that shows when your hair moves.
- Blue-black: Blue Velvet over dark hair for a cool sheen in the light.
How to apply blue hair dye at home
- Read the pack instructions and follow them, including any skin test they recommend.
- Protect your skin and bathroom. Gloves, barrier cream along your hairline, an old towel. Blue is one of the stronger stains; see how to get hair dye off your skin.
- Section and apply generously, combing through so every strand is coated.
- Leave for the time the pack says, then rinse with cool water until it runs nearly clear.
How long does blue hair dye last?
Usually a few weeks, depending on how light and porous your hair is and how often you wash. Blue often fades to a softer, more pastel or teal shade before it disappears.
How to keep blue hair bright
- Wash less and rinse cool. Stretch time between washes with Bodifying Dry Shampoo.
- Use colour-protecting care. Protective Shampoo and Protective Hair Conditioner help colour stay bright for longer.
- Protect from heat and sun with Heat Protection Shield.
- Top up early, before the blue fades far enough to turn green.
More in how to make hair colour last.
Other shades
Enhancing Color Pigments also come in Neon Pink, Bright Red and Fierce Copper, Rich Silver and Tropical Green.
Frequently asked questions
Will blue hair dye show on brown hair?
As a blue tint in daylight. For bright blue, the hair needs lightening first.
Can I put blue dye over black hair?
Yes, for a blue-black sheen in the light. It won't turn black hair bright blue.
Why is my blue hair green?
Yellow in the hair underneath mixes with the blue. Start on a paler, cooler base and top up before it fades too far.
How do I remove blue hair dye?
It fades with washing; a clarifying shampoo speeds it up. Blue can leave a stubborn tint on very light hair, so ask your colourist if you need it gone completely.
Is it vegan?
Yes. Every Insight product is vegan, cruelty-free and made in Italy.
About the author
Charlotte Read has spent six years in the hair industry with Insight Professional and holds a First Class BSc in Business Management and Marketing. She writes with reference to real salons across social media and the wider Insight community, and draws on the Insight office team, who between them bring over 100 years of combined experience on salon floors.
Where technical expertise is needed, Charlotte consults Lorraine Matic, Head of Insight UK Education, who brings over 38 years of global experience in colour, technique and hair science.