Sodium Ascorbyl Phosphate: does it work, and at what %?

How we grade Sodium Ascorbyl Phosphate

We check the disclosed concentration against the effective threshold from peer-reviewed dermatology literature and regulatory monographs, then weigh the formulation and any product-specific study. The grade is computed from the open rubric — re-run it on any ingredient list and you get the same letter. Also labeled as SAP.

Products with a disclosed effective dose

We haven't yet graded a product that discloses an effective dose of Sodium Ascorbyl Phosphate — most brands won't publish the concentration. As brands disclose (or get Verified), graded products will appear here. Browse the full index →

Common questions

What concentration of Sodium Ascorbyl Phosphate is effective?

On Visage Theory's rubric, Sodium Ascorbyl Phosphate reaches an effective dose at 1% and a strong, research-backed dose at 5%. Below that, the labeled benefit is unlikely no matter how good the marketing is.

Is more Sodium Ascorbyl Phosphate always better?

Not necessarily — past the effective range you mostly add irritation risk, not benefit. What matters is clearing the threshold in a stable formula, which is exactly what our grade checks.

How do I know a product actually contains an effective dose of Sodium Ascorbyl Phosphate?

Most brands list the active but hide the concentration. When the dose isn't disclosed we can't confirm efficacy, so we withhold a grade rather than guess. Products that disclose an effective dose are graded and listed below.