Ingredient review
Diammonium Citrate
INCI: DIAMMONIUM CITRATE
Diammonium Citrate is a safe, low-irritation pH adjuster that helps keep your skincare products stable and gentle on skin.
In plain English
Diammonium Citrate is a salt derived from citric acid and ammonia. In skincare, it's used in tiny amounts to control the pH (acidity level) of a product. A balanced pH helps your skin's protective barrier stay healthy and reduces the chance of irritation from other ingredients. It doesn't actively treat skin concerns itself, but it plays a supporting role in making formulas more effective and comfortable to use.
Review score
Safety, usefulness, and evidence
Potentially useful with some tradeoffs
The evidence base is useful, but some claims depend heavily on the formula.
Risk flags are low for most users, though the finished product can still irritate.
- Source
- synthetic
- Evidence
- moderate
- Irritation
- low
- Clogging risk
- low
Quick decision guide
Useful, but context matters
Diammonium Citrate is generally a lower-concern ingredient when the full formula suits your skin.
Plain-English read
Treat this as a practical screening step before you compare products that contain this ingredient.
- Step 1Start with the score, then check the irritation and clogging risk before judging Diammonium Citrate.
- Step 2Use the "Best for" and "Use caution if" sections to match the ingredient to your skin, not just to a marketing claim.
- Step 3If a product stings, breaks you out, or worsens irritation, judge the finished formula and stop using it even if the ingredient scores well.
Score terms in plain English
Irritation risk
lowLess likely to sting, burn, or bother most users, though sensitive skin can still react.
Clogging risk
lowLess likely to feel heavy or contribute to clogged pores for most skin types.
Evidence level
moderateThere is useful support, but formula details and claim strength still matter.
What it is
Diammonium Citrate is the diammonium salt of citric acid. It appears as a white crystalline powder and is synthetically produced for cosmetic use. Its primary job is to act as a buffering agent, meaning it resists changes in pH when small amounts of acid or base are added.
How it works
When added to a formula, Diammonium Citrate helps maintain a stable pH range (typically around 5.0–6.0, close to skin's natural pH). This stability ensures that active ingredients like vitamin C or AHAs work optimally without causing sudden pH shifts that could irritate skin. It also helps other preservatives function better, extending product shelf life.
Pros
Gentle pH balancer
Diammonium Citrate helps keep a product's pH close to skin's natural level (around 5.5), which supports a healthy skin barrier and reduces the risk of stinging or irritation.
Improves formula stability
By buffering pH, it prevents drastic changes that could degrade active ingredients or preservatives, helping your products stay effective longer.
Cons and cautions
No direct skin benefit
Unlike humectants or antioxidants, Diammonium Citrate doesn't hydrate, brighten, or protect skin. Its role is purely functional in the formula.
Potential for irritation at high levels
While safe at cosmetic concentrations, extremely high amounts could disrupt the skin's acid mantle. However, this is not a concern in properly formulated products.
Best for
- Anyone using pH-sensitive active ingredients like AHAs or vitamin C
- People with sensitive skin who benefit from well-buffered, gentle formulas
Use caution if
- Those with known ammonia sensitivity (though levels are extremely low and safe)
Usage tips
Safety summary
Diammonium Citrate is considered safe for use in cosmetics at concentrations up to 5% (though typical use is much lower). It has low irritation and sensitization potential. The CIR panel has reviewed it and found it safe as a pH adjuster.
Research notes
Research on Diammonium Citrate is limited to its function as a buffering agent. No peer-reviewed studies indicate toxicity or irritation at cosmetic levels. Its safety profile is well-established through regulatory review.
Common label clues
- Typical concentration
- Typically used at very low concentrations (under 1%) to adjust pH
- Regulatory status
- Approved for use in cosmetics by the FDA and the Cosmetic Ingredient Review (CIR) panel. No restrictions at typical concentrations.
- Common uses
- Cleansers, Toners, Leave-on creams, Hair care products
- Environmental note
- Synthetically produced, but biodegradable. No significant environmental concerns at cosmetic usage levels.
Good to know
- Diammonium Citrate is often used alongside citric acid and sodium citrate in buffer systems.
- It is considered safe by the Cosmetic Ingredient Review (CIR) panel at typical use levels.
Common questions
What is Diammonium Citrate in beauty products?
Diammonium Citrate is a salt derived from citric acid and ammonia. In skincare, it's used in tiny amounts to control the pH (acidity level) of a product. A balanced pH helps your skin's protective barrier stay healthy and reduces the chance of irritation from other ingredients. It doesn't actively treat skin concerns itself, but it plays a supporting role in making formulas more effective and comfortable to use.
What does Diammonium Citrate do in a beauty product?
When added to a formula, Diammonium Citrate helps maintain a stable pH range (typically around 5.0–6.0, close to skin's natural pH). This stability ensures that active ingredients like vitamin C or AHAs work optimally without causing sudden pH shifts that could irritate skin. It also helps other preservatives function better, extending product shelf life.
Is Diammonium Citrate safe for most people?
Diammonium Citrate is considered safe for use in cosmetics at concentrations up to 5% (though typical use is much lower). It has low irritation and sensitization potential. The CIR panel has reviewed it and found it safe as a pH adjuster.
Who should be careful with Diammonium Citrate?
Those with known ammonia sensitivity (though levels are extremely low and safe)
Research sources
Ingredient reviews are educational and are not medical advice. Patch test new products and ask a licensed clinician about persistent irritation, allergies, pregnancy-specific questions, or diagnosed skin conditions.