Side-by-side comparison

The Inkey List Niacinamide Serum vs The Inkey List Polyglutamic Acid Serum

Both are serums. They share a 70% active-ingredient overlap, so the real decision is about price, texture and the supporting ingredients. Here's the side-by-side.

70%Active overlap
The Inkey List
Niacinamide Serum
SerumBudgetMorning or evening
OilinessCongestionDark Spots

A 10% niacinamide serum with added hyaluronic acid for oil control and blemish support. A clean, affordable single-active option; broadly comparable to other 10% niacinamide serums with a slightly more hydrating base.

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The Inkey List
Polyglutamic Acid Serum
SerumBudgetMorning or evening
DehydrationDullnessDryness

A hydration serum using polyglutamic acid, which holds even more water than hyaluronic acid, layered with HA. A lightweight, plumping hydrator that works well over or under HA; an affordable way to trial the ingredient.

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The verdict

Which should you choose?

Both sit in the Budget tier, so cost isn't the deciding factor here — choose on texture, finish and the supporting ingredients. The The Inkey List leans toward Congestion, Dark Spots, Oiliness. The The Inkey List leans toward Dehydration, Dryness, Dullness.

The overlap

What they share

At 70% active overlap, these are the ingredients doing comparable work in both formulas:

Hyaluronic Acid
The formulation

Ingredient stacks, side by side

The Inkey List — top of the list

  • Aqua~50–80%
  • Niacinamide~5–25%
  • Glycerin~3–10%
  • Sodium Hyaluron…~2–6%
  • Pentylene Glycol~1.5–4%

The Inkey List — top of the list

  • Aqua~50–80%
  • Glycerin~5–25%
  • Polyglutamic Ac…~3–10%
  • Sodium Hyaluron…~2–6%
  • Propanediol~1.5–4%
  • Panthenol~1–2%

● marks ingredients that appear near the top of both lists. Percentages are positional estimates from INCI order, not disclosed doses.

At a glance

The specs

The Inkey ListThe Inkey List
CategorySerumSerum
Price tierBudgetBudget
Best forOiliness, Congestion, Dark SpotsDehydration, Dullness, Dryness
Usage notesMorning or eveningMorning or evening
Active overlap70% — Hyaluronic Acid
Questions

Common questions

Is the The Inkey List Niacinamide Serum or the The Inkey List Polyglutamic Acid Serum better?
Neither is clearly better — they overlap 70% on active ingredients and sit in the same price tier. The difference comes down to texture, finish and the supporting ingredients, so the right choice depends on your skin type and preferences.
What's the difference between the The Inkey List Niacinamide Serum and the The Inkey List Polyglutamic Acid Serum?
Both are serums that share Hyaluronic Acid. Where they differ: the The Inkey List targets Congestion, Dark Spots; the The Inkey List targets Dehydration, Dryness.
Are the The Inkey List Niacinamide Serum and The Inkey List Polyglutamic Acid Serum dupes for each other?
They share 70% active-ingredient overlap based on published INCI lists, so one can stand in for the other on the actives that matter — chiefly Hyaluronic Acid. A dupe matches the hero actives, not the full sensory experience, so expect differences in texture, fragrance and exact concentrations.
Can I use the The Inkey List Niacinamide Serum and The Inkey List Polyglutamic Acid Serum together?
They both fill the serum slot in a routine, so you'd normally pick one rather than layer both. If you want to use both, treat one as your daytime option and the other for evening, and patch-test when introducing anything new.
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85% overlap

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