Top 8 Best Spirulina Supplements for Immunity (2026)

⇄Compare all 8 picks side by sidefull score breakdown · strength & weakness · price▾

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All 8 picks side by side — one column per scoring criterion. Every row links to its full card below.

Product	Score	Dose vs Clinical Range25%	Purity & Contaminant Control25%	Label Transparency20%	Certifications & Sourcing15%	Value15%	Price & buy
#1 Nutrex Hawaii Pure Hawaiian Spirulina 500 mg TabletsBest Overall	8.8	9.02	9.31	9.02	8.62	7.4	$32-34~$0.50 per 6-tablet (3 g) servingOn AmazonFull review →
＋Full 3 g trial dose in one printed serving−Not USDA Organic certified
#2 Earthrise California Spirulina 500 mg TabletsBest Premium	8.6	9.02	9.02	9.61	8.0	6.2	$19-20~$0.64 per 6-tablet (3 g) servingOn AmazonFull review →
＋Only product declaring c-phycocyanin content−Highest cost per dose on the list
#3 Anthony's California Spirulina Powder, 8 ozBest US-Grown Powder	8.5	9.21	8.4	8.63	7.0	9.03	$19-20~$0.26 per 1-teaspoon (3 g) servingOn AmazonFull review →
＋California-grown, Product of USA−Not organic certified
#4 NOW Certified Organic Spirulina 1,000 mg Double Strength TabletsBest Organic Tablet	8.4	8.03	8.83	8.0	9.01	8.6	$13-14~$0.11 per 1,000 mg tabletOn AmazonFull review →
＋USDA Organic via QAI, Non-GMO Project verified−Printed serving is one tablet, a third of the studied dose
#5 Vimergy USDA Organic Spirulina Powder, 250 gBest Premium Organic Powder	8.3	9.21	8.83	7.6	9.01	6.4	$39-41~$0.48 per 1-scoop (3 g) servingOn AmazonFull review →
＋Full 3 g scoop, single ingredient−About $0.48 per dose, roughly three times the budget organic powders
#6 Micro Ingredients Organic Spirulina Powder, 1 lbBest Value Organic Powder	8.2	9.21	6.5	8.0	8.43	9.61	$19-21~$0.13 per 1-scoop (3 g) servingOn AmazonFull review →
＋Lowest cost per 3 g dose on the list−California Prop 65 lead warning printed on the label
#7 BulkSupplements Organic Spirulina Powder, 500 gBest Budget	8.1	9.21	7.8	6.6	7.6	9.42	$24-26~$0.15 per 1-teaspoon (3 g) servingOn AmazonFull review →
＋About $0.15 per 3 g dose−No protein, iron or phycocyanin disclosure
#8 Nutricost Organic Spirulina 500 mg Tablets, 240 CountBest Budget Tablet	8.0	7.4	8.2	7.6	8.62	8.8	$12-14~$0.05 per 500 mg tabletOn AmazonFull review →
＋About $0.05 per tablet−Six tablets to reach the studied dose

1. #1

   Best Overall
   

   Nutrex Hawaii Pure Hawaiian Spirulina 500 mg Tablets

   Nutrex Hawaii

   8.8/10SAC Product Score™ⓘ

   SAC Product Score™ — how it breaks downⓘ

   • Dose vs Clinical Range25%9.0
   • Purity & Contaminant Control25%9.3
   • Label Transparency20%9.0
   • Certifications & Sourcing15%8.6
   • Value15%7.4

   Hawaiian-pond spirulina that hits the full 3 g trial dose in one six-tablet serving, declares its iron and protein, and carries the longest seal list on the list.

   $32-34

   ~$0.50 per 6-tablet (3 g) serving

   Form

   Tablet, 500 mg each

   Serving

   6 tablets (3 g)

   Count

   400 tablets (66 servings)

   Disclosed per serving

   2 g protein, 3 mg iron, 60 mg sodium

   Other ingredients

   Silica, chicory inulin, vegetable magnesium stearate

   Seals

   Non-GMO Project, GFCO gluten-free, Certified Vegan, kosher, glyphosate residue free

   Cost per dose

   ~$0.50 per 3 g serving

   Pros

   • ＋Full 3 g trial dose in one printed serving
   • ＋Single named Hawaiian farm with stated third-party testing
   • ＋Iron, protein and sodium declared on the panel
   • ＋Longest list of real third-party seals in the group

   Cons

   • −Not USDA Organic certified
   • −Six tablets a day is a lot of swallowing
   • −Three excipients where the organic tablets have none

   Our take — It costs more than a bag of powder and it is not organic, but everything the science asks for is on the panel: 3 g per serving, a named controlled pond, third-party testing and disclosed iron and protein. If you buy one spirulina, buy this one.

   Check Nutrex on Amazon →Read the full review →
2. #2

   Best Premium
   

   Earthrise California Spirulina 500 mg Tablets

   Earthrise

   8.6/10SAC Product Score™ⓘ

   SAC Product Score™ — how it breaks downⓘ

   • Dose vs Clinical Range25%9.0
   • Purity & Contaminant Control25%9.0
   • Label Transparency20%9.6
   • Certifications & Sourcing15%8.0
   • Value15%6.2

   The only product here that prints its c-phycocyanin content, 165 mg per 3 g serving, from a single California farm; you pay for that transparency with the highest cost per dose on the list.

   $19-20

   ~$0.64 per 6-tablet (3 g) serving

   Form

   Tablet, 500 mg each

   Serving

   6 tablets (3 g)

   Count

   180 tablets (30 servings)

   Disclosed per serving

   165 mg c-phycocyanin, 2 g protein, 1.5 mg iron, 20 mg sodium

   Other ingredients

   Vegetable stearate, silica

   Seals

   Non-GMO, kosher (KSA), California Grown

   Cost per dose

   ~$0.64 per 3 g serving

   Pros

   • ＋Only product declaring c-phycocyanin content
   • ＋Full 3 g serving from a single California farm
   • ＋Iron, protein and sodium disclosed
   • ＋Non-GMO and kosher seals on the panel

   Cons

   • −Highest cost per dose on the list
   • −Not organic certified
   • −No third-party testing statement printed on the pack

   Our take — If you take spirulina for its phycocyanin, Earthrise is the only brand that tells you how much you are getting. It matches Nutrex on dose and origin quality and beats it on disclosure; it loses on price and on the absence of a printed testing claim. A premium, honest tablet.

   Check Earthrise on Amazon →Read the full review →
3. #3

   Best US-Grown Powder
   

   Anthony's California Spirulina Powder, 8 oz

   Anthony's Goods

   8.5/10SAC Product Score™ⓘ

   SAC Product Score™ — how it breaks downⓘ

   • Dose vs Clinical Range25%9.2
   • Purity & Contaminant Control25%8.4
   • Label Transparency20%8.6
   • Certifications & Sourcing15%7.0
   • Value15%9.0

   A California-grown powder with a full food-style Nutrition Facts panel, 3 g per teaspoon, batch-tested gluten-free, at about a quarter per dose.

   $19-20

   ~$0.26 per 1-teaspoon (3 g) serving

   Form

   Powder

   Serving

   1 teaspoon (3 g)

   Count

   8 oz (226 g), 75 servings

   Disclosed per serving

   2 g protein, 2.4 mg iron, 9 mg calcium, 45 mg potassium, 20 mg sodium

   Other ingredients

   None

   Seals

   Gluten free (batch tested), Non-GMO, vegan friendly, Product of USA

   Cost per dose

   ~$0.26 per 3 g serving

   Pros

   • ＋California-grown, Product of USA
   • ＋Full 3 g teaspoon dose for about $0.26
   • ＋Iron, calcium, potassium and sodium disclosed
   • ＋No excipients; single ingredient

   Cons

   • −Not organic certified
   • −No heavy-metal or microcystin testing claim on the pack
   • −Plain powder taste; needs a smoothie

   Our take — If you want to know where your algae grew and do not need an organic seal, this is the cheapest way to a disclosed, 3 g, US-grown dose. It ranks above the organic powders because origin and mineral disclosure beat a seal on a bare panel.

   Check Anthony's on Amazon →Read the full review →
4. #4

   Best Organic Tablet
   

   NOW Certified Organic Spirulina 1,000 mg Double Strength Tablets

   NOW Foods

   8.4/10SAC Product Score™ⓘ

   SAC Product Score™ — how it breaks downⓘ

   • Dose vs Clinical Range25%8.0
   • Purity & Contaminant Control25%8.8
   • Label Transparency20%8.0
   • Certifications & Sourcing15%9.0
   • Value15%8.6

   A QAI-certified organic 1,000 mg tablet with no excipients at all, from a brand with in-house testing labs; three tablets reach the trial dose for about a third of a dollar.

   $13-14

   ~$0.11 per 1,000 mg tablet

   Form

   Tablet, 1,000 mg each

   Serving

   1 tablet (1,000 mg)

   Count

   120 tablets (120 servings)

   Disclosed per serving

   1 g organic spirulina, protein under 1 g

   Other ingredients

   None

   Seals

   USDA Organic (QAI), Non-GMO Project Verified, GMP Quality Assured

   Cost per dose

   ~$0.11 per tablet

   Pros

   • ＋USDA Organic via QAI, Non-GMO Project verified
   • ＋No excipients at all
   • ＋GMP manufacturing with in-house labs
   • ＋Cheap: about $0.11 per 1,000 mg tablet

   Cons

   • −Printed serving is one tablet, a third of the studied dose
   • −No iron or phycocyanin disclosure
   • −Growing region not named on the pack

   Our take — If you want organic certification in a tablet, NOW is the pick: no binders, real seals, a testing-lab manufacturer and a low price. Take three to match the trials and it still costs about a third of a dollar a day.

   Check NOW on Amazon →Read the full review →
5. #5

   Best Premium Organic Powder
   

   Vimergy USDA Organic Spirulina Powder, 250 g

   Vimergy

   8.3/10SAC Product Score™ⓘ

   SAC Product Score™ — how it breaks downⓘ

   • Dose vs Clinical Range25%9.2
   • Purity & Contaminant Control25%8.8
   • Label Transparency20%7.6
   • Certifications & Sourcing15%9.0
   • Value15%6.4

   The premium organic powder: USDA Organic, OU kosher, gluten-free, vegan and paleo seals on a 3 g scoop, with a price to match.

   $39-41

   ~$0.48 per 1-scoop (3 g) serving

   Form

   Powder

   Serving

   1 scoop (3 g)

   Count

   250 g (8.8 oz), about 83 servings

   Disclosed per serving

   3 g spirulina algae, 2 g protein

   Other ingredients

   None

   Seals

   USDA Organic, kosher (OU), gluten free, vegan, paleo friendly

   Cost per dose

   ~$0.48 per 3 g serving

   Pros

   • ＋Full 3 g scoop, single ingredient
   • ＋USDA Organic plus kosher, gluten-free, vegan and paleo seals
   • ＋No excipients or additives

   Cons

   • −About $0.48 per dose, roughly three times the budget organic powders
   • −No iron or phycocyanin disclosure
   • −Growing region not printed on the pack

   Our take — Vimergy earns a mid-table spot on dose and seals. It does not beat the tablets on disclosure or the budget powders on price, so it is the pick for buyers who specifically want the fullest certification row on an organic powder.

   Check Vimergy on Amazon →Read the full review →
6. #6

   Best Value Organic Powder
   

   Micro Ingredients Organic Spirulina Powder, 1 lb

   Micro Ingredients

   8.2/10SAC Product Score™ⓘ

   SAC Product Score™ — how it breaks downⓘ

   • Dose vs Clinical Range25%9.2
   • Purity & Contaminant Control25%6.5
   • Label Transparency20%8.0
   • Certifications & Sourcing15%8.4
   • Value15%9.6

   A pound of USDA Organic spirulina for about thirteen cents a dose, with chlorophyll and protein on the panel; docked hard for the Prop 65 lead warning printed on the label.

   $19-21

   ~$0.13 per 1-scoop (3 g) serving

   Form

   Powder

   Serving

   1 scoop (about 3 g)

   Count

   1 lb, 151 servings

   Disclosed per serving

   3 g organic spirulina, 2 g protein, about 40 mg chlorophyll

   Other ingredients

   None

   Seals

   USDA Organic, cGMP, GMO free, third party lab tested

   Warning

   California Prop 65 lead warning printed on the label

   Cost per dose

   ~$0.13 per 3 g serving

   Pros

   • ＋Lowest cost per 3 g dose on the list
   • ＋USDA Organic, cGMP and third-party-lab-tested marks
   • ＋Chlorophyll and protein declared
   • ＋151 servings per bag

   Cons

   • −California Prop 65 lead warning printed on the label
   • −Growing region not named
   • −Plain powder taste

   Our take — If price per dose is your ranking, this wins. Our ranking weights contaminant control at a quarter of the score, and a printed lead warning costs it the podium. Buy it knowingly, or pay a little more for Anthony's California powder without the warning.

   Check Micro on Amazon →Read the full review →
7. #7

   Best Budget
   

   BulkSupplements Organic Spirulina Powder, 500 g

   BulkSupplements.com

   8.1/10SAC Product Score™ⓘ

   SAC Product Score™ — how it breaks downⓘ

   • Dose vs Clinical Range25%9.2
   • Purity & Contaminant Control25%7.8
   • Label Transparency20%6.6
   • Certifications & Sourcing15%7.6
   • Value15%9.4

   Half a kilo of USDA Organic spirulina, 167 teaspoon servings of 3 g, no additives, no warnings, for about fifteen cents a dose; the panel just does not tell you much.

   $24-26

   ~$0.15 per 1-teaspoon (3 g) serving

   Form

   Powder

   Serving

   1 teaspoon (about 3 g)

   Count

   500 g, 167 servings

   Disclosed per serving

   3 g organic spirulina powder

   Other ingredients

   None; allergens: none

   Seals

   USDA Organic; gluten free, soy free, dairy free, no added sugar, additive free

   Cost per dose

   ~$0.15 per 3 g serving

   Pros

   • ＋About $0.15 per 3 g dose
   • ＋USDA Organic, single ingredient, no allergens
   • ＋No Prop 65 warning
   • ＋167 servings per bag

   Cons

   • −No protein, iron or phycocyanin disclosure
   • −No third-party testing statement on the pack
   • −Growing region not named

   Our take — This is the sensible floor of the market: a real organic seal, a full 3 g teaspoon and a clean panel for fifteen cents. It cannot compete with the tablets on disclosure or origin, and it does not try.

   Check BulkSupplements.com on Amazon →Read the full review →
8. #8

   Best Budget Tablet
   

   Nutricost Organic Spirulina 500 mg Tablets, 240 Count

   Nutricost

   8/10SAC Product Score™ⓘ

   SAC Product Score™ — how it breaks downⓘ

   • Dose vs Clinical Range25%7.4
   • Purity & Contaminant Control25%8.2
   • Label Transparency20%7.6
   • Certifications & Sourcing15%8.6
   • Value15%8.8

   The cheapest organic tablet on the market, USDA and CCOF certified, no excipients; but at 500 mg a tablet you need six to reach the trial dose.

   $12-14

   ~$0.05 per 500 mg tablet

   Form

   Tablet, 500 mg each

   Serving

   1 tablet (500 mg)

   Count

   240 tablets (240 servings)

   Disclosed per serving

   500 mg organic spirulina

   Other ingredients

   None

   Seals

   USDA Organic, CCOF Certified Organic

   Cost per dose

   ~$0.05 per tablet

   Pros

   • ＋About $0.05 per tablet
   • ＋USDA and CCOF organic
   • ＋No excipients

   Cons

   • −Six tablets to reach the studied dose
   • −No disclosure beyond the spirulina amount
   • −No testing claim or origin on the pack

   Our take — Nothing is wrong with Nutricost's tablet; it is organic, clean and cheap. It ranks last because a 500 mg serving is far from the studied dose and the panel discloses the least of any product here. As a budget organic tablet it does its job.

   Check Nutricost on Amazon →Read the full review →

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