The original, what makes it special, the shelf parts we use and how to get closer. Add or swap parts and the score updates.
The original · Obagi
$130 · 1.0 fl oz (30 ml)
L-ascorbic acid at 15% in a propylene glycol and alcohol base, backed by a second, more stable vitamin C called ascorbyl glucoside.
Prices and listings checked Oct 28, 2026. Amazon prices change; the link shows today's price.
Step 2 · The build
Paula's Choice
Timeless Skin Care
Adds: Glycol solvent base
Naturium
Adds: Ascorbyl glucoside; Orange peel and grapefruit extracts
Partial credit means the part only partly matches that standout.
The 100 points
We split Professional-C Serum 15% into 4 standout parts. Each bar shows what the build earns.
Pure vitamin C at a mid strength for brightening, antioxidant defense and fine lines.
A stable vitamin C derivative that backs up the pure vitamin C.
Propylene glycol and similar solvents carry the acidic vitamin C into the skin and keep the formula light.
Citrus extracts add plant antioxidants and scent.
Optional
88 / 100. We have not found a shelf product that closes more of the gap yet.
Step 3 · Buy
One link per part. Each opens the retailer in a new tab.
Your build
Running total ~$70
Buy on Amazon (opens in new tab)Running total ~$97.95
Buy on Amazon (opens in new tab)Running total ~$118.95
View product (opens in new tab)Not an affiliate link.
Snapshot prices. Each link shows today's price.
One bottle instead of a build. Sorted by match score; scores use the same standouts as above.
Paula's Choice
Why it is close. The same 15% L-ascorbic acid level at pH 3, with vitamin E, ferulic acid and a peptide. It uses ethoxydiglycol and butylene glycol as solvents, close to the Obagi base.
Timeless Skin Care
Why it is close. Pure vitamin C at 20% in an ethoxydiglycol and propylene glycol base, plus vitamin E and ferulic acid. It is stronger than 15%, so it may sting more on reactive skin.
Naturium
Why it is close. Combines a vitamin C derivative (sodium ascorbyl phosphate) with some L-ascorbic acid and a fruit extract blend that includes citrus. It is a gentler, lower-strength take on the same idea.
Not an affiliate link.
Paula's Choice
Running total
Buy on Amazon (opens in new tab)No gain nowPaula's Choice
Timeless Skin Care
Adds: Glycol solvent base
Running total
Buy on Amazon (opens in new tab)No gain nowTimeless Skin Care
Naturium
Adds: Ascorbyl glucoside; Orange peel and grapefruit extracts
Running total
View product (opens in new tab)Not an affiliate link.
No gain nowNaturium
Topical L-ascorbic acid absorbs into skin only at a low pH (below 3.5), with absorption rising up to 20%.
Pinnell 2001 · Dermatol SurgA 15% L-ascorbic acid serum reduced roughness and redness over 56 days in an open-label study.
Lintner 2020 · J Cosmet DermatolReviews find topical vitamin C smooths skin and lightens melasma and photoaging with long-term use.
Correia 2023 · J Cosmet DermatolPropylene glycol, aqua/water/eau, ascorbic acid, alcohol denat., ascorbyl glucoside, citrus aurantium dulcis (orange) peel extract, citrus paradisi (grapefruit) fruit extract, caprylyl/capryl glucoside, fragrance (parfum), citric acid, benzyl benzoate, amyl cinnamal, limonene, hexyl cinnamal.
We split Professional-C Serum 15% into 4 standout parts worth 100 points in total. The build earns 88 of a possible 100. A full 100 needs every standout fully covered.
Paula's Choice C15 Super Booster 15% Vitamin C Serum by Paula's Choice is our closest single-product match at 71 out of 100 for ~$70 (0.67 fl oz (20 ml)). It shares L-ascorbic acid 15%, Glycol solvents.
Professional-C Serum 15% costs $130 for 1.0 fl oz (30 ml). The closest dupe costs ~$70, a saving of about $60. Prices change, so check the seller page.
No. Dupes share the key actives but can differ in concentration, vehicle and supporting ingredients. Missing from this one: Ascorbyl glucoside, Citrus extracts. See our methodology for how we score.
Obagi · serum
$74.94our build, 2 partsOriginal $155, build $74.94.
Timeless Skin Care + La Roche-Posay
SkinBetter Science · exfoliant
~$37our build, 4 partsOriginal $125, build ~$37.
The Ordinary
SkinBetter Science · serum
~$52.98 + check priceour build, 4 partsOriginal ~$195, build ~$52.98 + check price.
CeraVe + The Ordinary + Vanicream + Paula's Choice