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
$155 · 1.0 fl oz (30 ml)
L-ascorbic acid at 20%, the top strength for pure vitamin C, in a propylene glycol and ethoxydiglycol base.
Prices and listings checked Oct 28, 2026. Amazon prices change; the link shows today's price.
Step 2 · The build
Timeless Skin Care
La Roche-Posay
Adds: Sodium hyaluronate
Partial credit means the part only partly matches that standout.
The 100 points
We split Professional-C Serum 20% into 5 standout parts. Each bar shows what the build earns.
Pure vitamin C at the strength linked to the highest skin levels. It brightens, fades dark spots and adds antioxidant defense.
Holds water in the skin so a strong vitamin C feels less drying.
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
85 / 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 $27.95
Buy on Amazon (opens in new tab)Running total $74.94
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.
Timeless Skin Care
Why it is close. The closest match: 20% L-ascorbic acid in the same ethoxydiglycol and propylene glycol base, with sodium hyaluronate. It adds vitamin E and ferulic acid and has no added fragrance.
The Ordinary
Why it is close. Pure vitamin C at 23% in a water-free silicone and oil base with hyaluronic acid spheres. The texture is gritty and it can tingle, but it is the cheapest high-strength option.
Not an affiliate link.
La Roche-Posay
Why it is close. Pure vitamin C at 12% with sodium hyaluronate in a lighter silicone serum. It is gentler than 20%, so it gives less of the high-strength effect.
Not an affiliate link.
Timeless Skin Care
Running total
Buy on Amazon (opens in new tab)No gain nowTimeless Skin Care
La Roche-Posay
Adds: Sodium hyaluronate
Running total
View product (opens in new tab)Not an affiliate link.
No gain nowLa Roche-Posay
The Ordinary
Running total
View product (opens in new tab)Not an affiliate link.
No gain nowThe Ordinary
Topical L-ascorbic acid absorbs into skin only at a low pH, with 20% giving the highest tissue levels.
Pinnell 2001 · Dermatol SurgTopical vitamin C improved photoaged skin in a double-blind 6-month trial.
Humbert 2003 · Exp 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, ethoxydiglycol, phenoxyethanol, sodium hyaluronate, sorbitol, citrus aurantium dulcis (orange) peel extract, citrus paradisi (grapefruit) fruit extract, fragrance (parfum), caprylyl/capryl glucoside, calcium hydroxide, zinc chloride, citric acid, benzyl benzoate, amyl cinnamal, limonene, hexyl cinnamal.
We split Professional-C Serum 20% into 5 standout parts worth 100 points in total. The build earns 85 of a possible 100. A full 100 needs every standout fully covered.
Timeless 20% Vitamin C + E Ferulic Acid Serum by Timeless Skin Care is our closest single-product match at 81 out of 100 for $27.95 (1 fl oz (30 ml)). It shares L-ascorbic acid 20%, Ethoxydiglycol and propylene glycol base, Sodium hyaluronate.
Professional-C Serum 20% costs $155 for 1.0 fl oz (30 ml). The closest dupe costs $27.95, a saving of about $127.05. 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
~$118.95our build, 3 partsOriginal $130, build ~$118.95.
Paula's Choice + Timeless Skin Care + Naturium
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