Interaction Map · Free

Which actives
work together?

Some ingredients boost each other. Some cancel out. A few just irritate your skin when layered. The interaction map shows which pairs to combine, which to split between morning and night, and which to keep apart — grounded in a verified database, not guesswork.

Open the Map → How it works

Compatibility, answered from data.

✓
Pairs that help

Green pairings that genuinely support each other — like vitamin C with niacinamide, or retinol with ceramides — so you can build a routine that compounds instead of competing.

⚠
Pairs to separate

Clashes flagged clearly, with the usual fix — often just splitting the two across morning and evening rather than dropping either one.

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Grounded in the catalogue

Every verdict comes from a verified ingredient database. The map only reports relationships that exist there — and tells you plainly when there is no known conflict.

🧴
From a real product

Decode a product's ingredient list and the map auto-populates, so you can check what is actually in the bottle — or add ingredients by hand to test a combination first.

What the map tells you.

🟢
Clear pair-by-pair verdicts
Each combination reads as pairs-well, separate, or avoid — no vague "it depends." Where two actives clash, you see why.
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AM/PM separation guidance
Most conflicts are solved by timing, not by cutting a product. The map points you to which active belongs in the morning and which at night.
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A link to the full guide
Every ingredient in the map links through to its glossary entry, so a flagged conflict is a starting point for understanding, not a dead end.
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Straight from a product's label
Decode a product and the map fills itself in from the decoded actives — check compatibility against what is genuinely in the formula.
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No invented conflicts
If two ingredients have no known issue, the map says so. It will not manufacture a clash to look thorough — the honesty is the point.
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Private by design
No login, no account, nothing sent to a server. Whatever you check stays in your browser.

Three steps, a few seconds.

Add your ingredients

Decode a product to auto-populate the map, or type the actives you want to check — retinol, vitamin C, an acid, whatever is on your shelf.

Read the pairings

Each combination shows as pairs-well, separate, or avoid, drawn from the verified database — with the reason and the AM/PM fix where one applies.

Adjust and build

Split clashing actives across morning and night, lean into the pairings that help, and take any flag through to its full ingredient guide.

Questions.

Can you use retinol and vitamin C together?
Skin Stacker's interaction map flags retinol and vitamin C as a caution rather than a clean pairing — each lists the other as best avoided in the same layer. The usual fix is to separate them: vitamin C in the morning (where it also supports your SPF) and retinol at night. Used on alternate routines like that, both can sit comfortably in the same regimen; it is layering them at the same time that tends to cause irritation and can reduce the stability of the vitamin C.
What should you not mix with retinol?
In the catalogue, retinol is flagged to avoid combining in the same layer with vitamin C, glycolic acid, salicylic acid, and benzoyl peroxide — mostly because stacking strong actives raises the irritation load and, with benzoyl peroxide, can degrade the retinoid. Retinol pairs well with buffering, barrier-supportive ingredients instead: ceramides, squalane, and panthenol. The map shows these as green pairings so you can build around the retinol rather than against it.
Does niacinamide conflict with anything?
No. Niacinamide carries no avoid flags in the catalogue — it is one of the most cooperative actives there is, pairing well with hyaluronic acid, ceramides, zinc, and yes, vitamin C. The old idea that niacinamide and vitamin C cancel each other out is not supported for modern formulations, and the map lists them as compatible rather than conflicting.
How does the interaction map decide what conflicts?
It reads Skin Stacker's verified ingredient database. Every ingredient carries its own pairs-well and avoid-combining lists, and the map only reports relationships that actually exist there — so when there is no known conflict, it tells you that plainly instead of inventing one. You can auto-populate it by decoding a product's ingredient list, or add ingredients yourself to test a combination before you buy or layer it.
Is this a substitute for a dermatologist?
No. The interaction map is educational — it catches common ingredient clashes and shows sensible pairings, but it cannot examine your skin, account for a specific medical condition, or replace personalised clinical advice. For persistent concerns or a reaction that worries you, see a qualified dermatologist.

Stop guessing what layers.

No ads, no affiliates, no product to sell you — just an honest map of what works together, what to separate, and what to keep apart.

Open the Map →