iHerb vs Quest Diagnostics
iHerb (iherb.com) and Quest Diagnostics (questdiagnostics.com) are stores in related niches (Vitamins & Supplements and Health) in the AdLibrarySpy index. iHerb gets more monthly visits than Quest Diagnostics: about 48M vs 16M.
The facts we hold on both, side by side. Checked November 4, 2026.
In short
- iHerb gets more monthly visits than Quest Diagnostics: about 48M vs 16M.
- iHerb runs more live Meta ads than Quest Diagnostics: 805 vs 2.
- iHerb advertised on more days in the past 12 months: 38 vs 5.
| Fact |  iHerb |  Quest Diagnostics |
|---|---|---|
| Monthly visits (SimilarWeb) | 48M (Sep 2026) | 16M (Sep 2026) |
| Live Meta ads | 805 | 2 |
| Store created | Dec 2016 | Dec 2016 |
| Based in | United States | United States |
| Niche | Vitamins & Supplements | Health |
Questions shoppers ask
- What is the difference between iHerb and Quest Diagnostics?
- iHerb gets more monthly visits than Quest Diagnostics: about 48M vs 16M. iHerb runs more live Meta ads than Quest Diagnostics: 805 vs 2. iHerb advertised on more days in the past 12 months: 38 vs 5.
- Do iHerb and Quest Diagnostics sell the same things?
- Both are listed in related niches: iHerb in Vitamins & Supplements, Quest Diagnostics in Health.
Facts from the Meta Ad Library, SimilarWeb, Trustpilot and each store; a fact only one of them has is left out. Is iHerb legit? · Is Quest Diagnostics legit?