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Vitamin C Forms and Stated Strengths

Ascorbic acid is pure vitamin C; THD ascorbate is a derivative. Compare percentages within the same form, not as a results ranking. Neither concentration nor ingredient overlap predicts irritation or stability.

By Nora Ellison · Updated

Choose by form before percentage

Compare ascorbic acid and THD ascorbate claims without treating their percentages as equivalent potency. These 3 records have stated concentrations; undisclosed values are unknown, not zero. We do not measure potency, stability, absorption or individual tolerance.

Read the practical guide · Filter exact forms and percentages · Compare purpose-based alternatives.

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Ascorbic Acid (Vitamin C)

23% Ascorbic Acid (Vitamin C) — Manufacturer-stated named active; percentage basis not independently measured.

13% Ascorbic Acid (Vitamin C) — Manufacturer-stated named active; percentage basis not independently measured.

Vitamin C (THD Ascorbate)

15% Vitamin C (THD Ascorbate) — Manufacturer-stated named active; percentage basis not independently measured.

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