This question almost never arrives as a question about pH. It arrives as a feeling: you rinse, you reach for the towel, and by the time you are dry your face has gone tight and slightly squeaky. Then you go looking for a reason and the internet hands you the word alkaline.
Alkaline means a pH above 7, and every bar of true soap is alkaline — that is not a flaw in it, it is the definition of it. Soap is what you get when a fat meets an alkali. Take the alkali away and you have not got a milder soap, you have got something that is not soap.
Which does not settle whether it suits you. That part depends on your skin, and I sell a bar for each answer, so I have no side to take here.
Why does my skin feel tight after washing?
Because the wash removed more of your skin's own oil than it needed to, and the surface is drying faster than usual as a result. It is a real sensation, not imagined, and it is information. Tight within two minutes of rinsing means the cleanser is too much for that skin, or the water was too hot, or both.
Two things make it worse and neither of them is the soap. Very hot water, which strips faster than anything in the bar does. And the gap afterwards: skin left bare for ten minutes after a wash feels considerably tighter than skin that got something on it while it was still damp.
Is alkaline soap bad for your skin?
No, not as a category. It is bad for some skin and good for other skin, which is a much less satisfying answer than the internet usually gives. Skin that runs oily generally handles a higher pH well and often likes the properly-clean feeling. Skin that goes tight and papery does better with a milder bar and more oils left in it.
What is the pH of skin?
Roughly 4.5 to 5.5 — slightly acidic, and it varies by person, by body part and by time of day. Your forearm and your forehead are not the same reading. Wash with anything alkaline and that surface number goes up for a while, then drifts back down on its own over the next few hours.
That drift back is the part the scare articles leave out. It is not a permanent state change. It is the same skin doing what it does, on a schedule, and it has been doing it after every wash of your entire life.
What pH should handmade soap be?
Somewhere around 9 to 10 if it is soap. Below about 8 a bar of true soap starts coming apart chemically — the reaction runs backwards, the fatty acids come free, and you end up with a soft, greasy, spoiling brick. Which is why the "pH 5.5" bars in the pharmacy are almost never soap at all.
| What | Roughly where it sits |
|---|---|
| Skin surface | 4.5 – 5.5, slightly acidic |
| A bar of true soap, any maker | 9 – 10 |
| A pharmacy "pH 5.5 beauty bar" | About 5.5, and built from synthetic detergents rather than soap |
| Plain water | 7, or whatever your utility sends you |
So what does "pH neutral" mean on a bar of soap?
On a cleanser label it is shorthand for "formulated at the mild end", not a laboratory reading, and it gets used loosely across the whole industry. I use it that way myself on the Rose & Calendula bar, and I would rather say plainly what that does and does not mean than leave you to guess.
What it means on my bench: that bar is made to be the gentler of the two, with more oils left unreacted in the finished bar so it takes less off your skin. What it does not mean is that I have published a measured pH for it, because I have not, and I am not going to invent a number to make this page look more rigorous. If and when I have a meter reading for both bars, it goes on the product pages.
Which bar suits which skin, then?
If you shine by midday, the Balancing Loofah Soap. If you go tight and flaky, the Rose & Calendula Loofah Soap. Both are alkaline, because both are soap. The difference is how much of the oil stays in the bar rather than going down the drain with the lather.
If it is your whole face routine you are sorting out rather than one bar, the Balancing Skincare Routine is the four-step version of the first of those, and the broader question of matching a bar to a skin is in how to choose a bar of soap for your skin.
What actually stops the tight feeling?
Turn the water down first. Lukewarm, not hot — this is free, it is immediate, and for a lot of people it is the entire problem. Then shorten the gap: put your cream on while your skin is still damp, within a minute of the towel, not after you have got dressed and answered two emails.
Then, if it is still happening, change the bar. In that order, because the first two cost nothing and the third costs $21.99.
Is a high pH the reason handmade soap costs what it does?
No, and the two things get muddled constantly. The pH is chemistry that every soapmaker on earth is stuck with. The price is time, quantity and what stays in the bar, which is a completely separate accounting and one I have set out in full in why handmade soap costs more than a drugstore bar.
The short version of this whole page: alkaline is not a warning label. It is a description of what soap is. What you are choosing between is not acid and alkali, it is how much your particular skin wants taken off it.
Cosmetic products. Not intended to diagnose, treat, cure or prevent any disease.