Fish oil, krill oil, cod liver oil, algae oil — they all deliver omega-3s, but they are not interchangeable. Here is how they actually differ, and which is worth the price.
The comparison
| Source | Best for | Watch out for |
|---|---|---|
| Standard fish oil | Best value per gram of EPA+DHA | Low-concentration products need many capsules |
| Krill oil | Smaller capsules, fewer burps | Much less EPA+DHA per capsule, much higher price |
| Cod liver oil | Also supplies vitamins A and D | Vitamin A adds up — do not double up carelessly |
| Algae oil | Vegans and vegetarians | Pricier; check EPA as well as DHA |
Krill oil: the honest math
Krill oil is marketed on better absorption because its omega-3s come bound to phospholipids. There is something to that. But krill capsules typically contain far less EPA+DHA than fish oil capsules while costing several times more — so on a per-gram-of-omega-3 basis, the absorption edge rarely closes the price gap. Where krill genuinely wins is tolerability: smaller capsules and fewer fishy repeats.
Algae oil is not a compromise
Worth knowing: fish do not make omega-3s, they accumulate them from algae. Algae oil goes straight to the source, so it is a legitimate first-choice option rather than a vegan consolation prize. Just check that the product supplies EPA and not only DHA.
Omega-3 Fish Oil (e.g. Nordic Naturals, NOW)
- Compare on combined EPA + DHA per serving, not capsule count
- Third-party testing (IFOS, USP, NSF) covers purity and freshness
- 1–2 g EPA+DHA daily is a common supplemental range
Best value per gram of EPA+DHA
Check Price →Algae Oil Omega-3 (e.g. Nordic Naturals Algae, Testa)
- Goes to the original source — fish get omega-3s from algae
- Check it supplies EPA as well as DHA
- No fishy aftertaste; no sustainability concerns about fishing
Premium · plant-based
Check Price →Bottom line
For most people, a well-tested standard fish oil gives the most omega-3 per dollar. Choose algae if you avoid fish, and krill only if capsule size and burping are what keep you from taking it at all — a supplement you actually take beats a cheaper one you abandon. More detail in our omega-3 label guide.