There are three kinds of hair color, and the honest difference between them comes down to two things: how long the color stays, and how much it changes your hair to put it there. Temporary color sits on the surface and rinses out the next time you shampoo. Semi-permanent soaks into the hair and fades over a month or two. Permanent color mixes with a developer to change the hair itself, and it doesn't leave until it grows out.
Blendry is the first kind. I'll say that at the top because it decides everything else here. If you want a color that's still there at the end of the summer, this comparison is going to point you somewhere other than us, and I'd rather you walk away with the right thing than the Blendry thing.
Temporary color sits on the surface
This is the lowest-commitment color there is. The color sits on the outside of the hair instead of soaking in, so it comes out the next time you wash. One shampoo and you're back to your starting hair.
With Blendry that's the whole design. You mix a Color Drop between your fingers, or mix a few in a bowl, apply it with the Fingertip Applicator or Mascara Wand, then air dry for 5 minutes or blow dry for 30 seconds and brush it through. There's no developer and no rinse. You let it dry and brush it out smooth. Blendry is cruelty-free and ammonia-free, made with zero peroxide, which is the short way of saying it isn't doing anything permanent to your hair.
Temporary color shows up on any base, but your starting color changes how it reads. On light or bleached hair a Color Drop reads close to true. On dark brown or black hair the same Color Drop reads as a tint or a sheen you catch in the light, not a neon slab. That's just how color behaves on dark hair, which is why you test a small section first before you take it to your whole head.
Semi-permanent soaks in and fades
The color soaks into the cuticle, the outer layer of the hair, so it holds through washes and fades out over about four to eight weeks. It fades soft, which is the part people like about it. There's no harsh grow-out line. The color just gets quieter until one day it's gone.
It doesn't use a developer either, and this is where the honesty matters. Deposit-only semi-permanent color doesn't need bleach as a rule. What needs bleach is a vivid result on dark hair. If your hair is dark brown and you want a bright teal that actually looks bright, you have to lighten first, and that's true whether the color is semi-permanent or temporary. So be a little suspicious of anyone who sells you their color as the one that skips bleach while everybody else's needs it.
The trade you're making with semi-permanent is a rinse and a commitment. After it processes you rinse it out, and then you live with the color for a few weeks whether your plans change or not.
Permanent changes the hair itself
Permanent color is the big commitment, and the developer is the reason. It mixes with a developer, which is peroxide, and most permanent formulas add ammonia. Together they open the cuticle and swap out some of your natural color for the new shade. That's why it covers gray and why it doesn't wash out. It grows out instead, so a line shows at the root after a few weeks and you go back to keep it up.
Because the developer does some lightening on its own, permanent color can go a few shades lighter with no separate bleach. A dramatic jump, dark brown to platinum, still needs a bleach step first. Going darker or covering gray needs no bleach at all.
This is the one that truly changes your hair, and that's the whole point of it. If you need gray coverage or a color you won't have to think about for six weeks, permanent earns its place. It also carries the most damage risk of the three, because opening the cuticle and pulling color out is hard on hair in a way that a surface tint never is.
Side by side
The same six questions, answered for each:
| Question | Temporary (Blendry) | Semi-permanent | Permanent |
|---|---|---|---|
| How long it lasts | One wash. It's gone when you next shampoo. | About 4 to 8 weeks, fading as you wash. | Until it grows out. Roots show in a few weeks. |
| Developer or peroxide | None. | None. | Yes, peroxide. Most add ammonia too. |
| Bleach needed | No. Reads as a tint on dark hair. | Only for a vivid shade on dark hair. | Not to go darker or cover gray. A big lift to light still needs it. |
| Rinse step | No rinse. Dry it, then brush through. | Yes, rinse after it processes. | Yes, rinse, then condition. |
| On dark hair | Shows as a tint or sheen, not neon. | Same, unless you pre-lighten first. | Goes darker or covers gray with no bleach. Going lighter needs lift. |
| Best for | One night, an event, testing a color, changing your mind. | A few weeks of color without constant upkeep. | A lasting change and gray coverage you're sure about. |
Dark hair and a Friday night out
Say your hair is dark brown, you've got something on Friday night you want to look a little different for, and a meeting Monday morning where you'd rather look like yourself. This is the exact situation temporary color is built for.
With Blendry you'd mix a Color Drop on Friday evening. A saturated shade shows best on dark hair, so something like Amethyst, which is Velvet Purple mixed one to one with Mix Foundation, reads as a violet sheen through dark brown, strongest where the light catches it. Test a small section first so you know how it lands on your hair. Apply it, air dry 5 minutes or blow dry 30 seconds, brush it through, and you're out the door. No rinse. Sunday night you shampoo and it's gone. Monday you're back to plain dark brown and nobody at the meeting is any the wiser.
Run that same Friday through the other two options and you can see why they don't fit. Semi-permanent would still be with you at the Monday meeting, and for a month of meetings after that. Permanent would leave a root line growing out until fall, all for one Friday night. For a night that's meant to be temporary, only temporary color actually ends when the night does.
Picking the one that fits
Sort it by how much you want to commit and the choice mostly makes itself.
Go temporary if you're trying a color for the first time, if it's for one night or one event, if your work or school wants your hair a normal color on Monday, or if you change your mind a lot and want the freedom to. It's also the easy answer when your hair is dark and you don't want to bleach, as long as you're happy with a tint instead of a billboard.
Semi-permanent makes sense when you want the color to stay a few weeks without redoing it, and you don't mind rinsing after you apply and living with a slow fade in between.
Permanent is the pick when you need gray coverage, or you want a lasting change you're sure about and you'll keep up with the regrowth. It lasts the longest and asks the most of your hair in return.
A quick word on cost, since that's part of the commitment too. A Color Drop is $21, Mix Foundation is $12, and the Tool Kit with the applicators is $9. If you're building a few shades, a 3-pack of Color Drops is $55 and a 5-pack is $90. US orders ship free by express over $45 and free by priority over $85, and Blendry ships worldwide in USD with other rates worked out at checkout. Orders go out in one to three business days.
If bleach is the part you're trying to avoid, how to dye your hair without bleach at home is the longer walkthrough. If you want the mechanics of the wash-out itself, temporary hair color that washes out covers how the one-wash part works. And once you've decided, the Color Drops are in the shop.