The short answer
Choose on the price per 100 g, the phycocyanin content and whether contaminant test results are published. And do not buy spirulina for its protein or its vitamin B12: at the real dose of 3 g a day, it provides 2 g of protein, and its B12 is a pseudo-vitamin that the body does not use. The price runs from 4.50 EUR per 100 g for Bioptimal, grown in India, to 39.78 EUR for a small bottle of Dynveo, grown in France: nearly nine times more. Origin and published test results explain part of the gap, but not all of it.
Two selling points to dismiss straight away
The 67% protein figure means nothing
It is accurate: spirulina is two-thirds protein. But the recommended dose is 3 g a day, which gives 2 g of protein, the equivalent of eight grams of chicken breast. Presenting spirulina as a protein source means reasoning per 100 g on a product eaten by the pinch.
If protein intake is your goal, our guide to plant proteins gives the sources that really count.
Its vitamin B12 is inactive
Spirulina contains pseudo-vitamins B12, analogues that the human body does not absorb and that can also distort the interpretation of a blood test. A vegan who counts on spirulina for B12 believes they are covered without being so: this is the most damaging scenario on this subject. The detail is in our ranking of foods high in vitamin B12.
What spirulina really has going for it, and our guide to its benefits sorts it out: an interesting density of iron and phycocyanin, a modest documented benefit, and a reputation that goes well beyond its evidence.
The price per 100 g, recorded on 24/09/2026
Comparing a bottle of 90 tablets with a 250 g pouch makes no sense. The useful unit is the price per 100 g of algae, and the cost of the daily 3 g dose.
| Product | Quantity | Price | Price / 100 g | Cost per day | Supply |
|---|---|---|---|---|---|
| Bioptimal, powder, India | 1 kg | 44.95 EUR | 4.50 EUR | 0.13 EUR | 333 days |
| Bioptimal, 1,200 tablets of 500 mg, India | 600 g | 37.95 EUR | 6.33 EUR | 0.19 EUR | 200 days |
| Nat&Form, 200 tablets of 500 mg, origin not stated | 100 g | 11.90 EUR | 11.90 EUR | 0.36 EUR | 33 days |
| Dynveo, powder, France | 250 g | 54.90 EUR | 21.96 EUR | 0.66 EUR | 83 days |
| Dynveo, 500 tablets of 500 mg | 250 g | 59.90 EUR | 23.96 EUR | 0.72 EUR | 83 days |
| Dynveo, 200 tablets | 100 g | 28.90 EUR | 28.90 EUR | 0.87 EUR | 33 days |
| Dynveo, powder | 90 g | 26.90 EUR | 29.89 EUR | 0.90 EUR | 30 days |
| Nutri&Co, 120 tablets of 500 mg | 60 g | 19.90 EUR | 33.17 EUR | 1.00 EUR | 20 days |
| Dynveo, 90 tablets | 45 g | 17.90 EUR | 39.78 EUR | 1.19 EUR | 15 days |
Origin makes the first gap. A spirulina grown in India and sold by the kilo costs five times less than the best French spirulina in the table. Format makes the second. At Dynveo, from 21.96 to 39.78 EUR per 100 g depending on the packaging, an 81% gap for the same algae from the same brand. The powder has a pronounced taste that the tablets avoid: it is the only real trade-off, and it costs 9% more.
The two quality criteria that count
Contaminant tests, and this is not a detail
Spirulina fixes the heavy metals present in its growing medium. This is not a theoretical worry: harvests from Lake Texcoco in Mexico had to be stopped because of heavy metal accumulation, and production from Lake Chenghai in China saw a lead contamination scandal.
Dynveo and Nutri&Co grow in France and publish batch tests: heavy metals, pesticides, microcystins, microbiological checks. Bioptimal grows in Tamil Nadu, India, publishes a certificate of analysis on its page and states that heavy metals are regularly checked by an independent laboratory. This is the first criterion to check, before price. A spirulina with no published tests, whatever its stated origin, has no place in a daily course. That is the case for Nat&Form, whose page gives neither the origin of the algae nor its tests: cheaper than the French spirulinas, it does not pass this first filter.
Phycocyanin, the only marker of richness
It is the blue pigment of the algae, and its content serves as an indicator of growing quality. A standard spirulina contains 15 to 20%. Dynveo states 25 to 31% depending on the batch, Nutri&Co 20 to 25% guaranteed. Both are above standard, with a measurable advantage for the first. Bioptimal and Nat&Form do not publish this content.
A point of honesty: a high phycocyanin level signals good growing, it does not demonstrate a superior clinical benefit. It is a marker, not proof.
Our sources
- Official Dynveo, Nutri&Co, Bioptimal and Nat&Form pages, viewed on 24/09/2026: origin, form, phycocyanin content, formats, prices and published test results.
- The prices per 100 g and daily costs are calculated from these records, based on the recommended dose of 3 g a day.