Where Testosil takes this matchup
Both sellers publish their own numbers, and both were read on Aug 30, 2026.
The dose. Testosil puts 300mg of KSM-66 ashwagandha in every serving, the same per-serving amount used in the published, randomized, double-blind study behind the formula. Testosil's own comparison table puts TestoPrime at 55.67mg of the same extract.
The guarantee. Testosil's money-back guarantee runs with no deadline: all bottles come back, opened and unopened, at any time. TestoPrime's own site states a 60-day window.
The label. Testosil prints its Supplement Facts panel on the bottle, serving size 4 capsules, 30 servings per container, and the photograph of that panel is further down this page. TestoPrime's own site publishes no milligram amount for any of its 12 ingredients.
Testosil is the offer this bench reviewed in full, and the only one carrying a link here.
Testosil against TestoPrime, row by row
The rows below come from Testosil's own comparison table, read Aug 30, 2026, cell for cell. The guarantee row is the window each seller publishes on its own site.
| Attribute | Testosil | TestoPrime |
|---|---|---|
| Money-back guarantee | Lifetime, no deadline | 60 days |
| Ashwagandha-KSM-66 per serving | Yes, 300mg | Yes, 55.67mg |
| Clinically Validated Ingredients | Yes | No |
| Doctor Recommended | Yes | No |
| Magnesium | Yes | No |
| Pantothenic Acid | Yes | No |
| L-Arginine HCL | Yes | No |
| Asian Ginseng Extract | Yes | No |
Rows quoted from Testosil's own comparison table, read Aug 30, 2026 (trademark symbols dropped); that table also names five other brands, outside the scope of this pairing.
Guarantee row: Testosil's own guarantee terms and TestoPrime's own site, both read Aug 30, 2026.
Both ashwagandha quotes, word for word: 300mg against 55.67mg
Testosil's own table puts a number next to both bottles, and one of them is more than five times the other.
Ashwagandha-KSM-66: Testosil Yes, 300mg. TestoPrime Yes, 55.67mg.
Testosil's 300mg matches the per-serving dose used in the published Wankhede et al. 2015 training study behind its own formula, already verified in our full Testosil review.
"The world’s most powerful and pure form of ashwagandha that is clinically-tested and shown to support existing testosterone for improved energy, weight loss efforts, digestion, cognitive ability, and muscle gains."
That is TestoPrime's complete description of its own KSM-66 ashwagandha extract.
TestoPrime's own site publishes no milligram amount for this extract, or for any of its other 11 ingredients.
Testosil's 300mg is the exact per-serving dose used in the clinical study it cites, and it is printed on the Supplement Facts panel of the bottle.
Both guarantee quotes, word for word: no deadline against 60 days
This is where the two offers separate, and both quotes below are the sellers' own.
"a 100% satisfaction LIFETIME money-back guarantee... return all bottles (opened and unopened), at any time... a full refund of the purchase price for all unopened bottles and one opened bottle."
No deadline: the window does not close on day 30 or day 60. The refund covers every unopened bottle plus one opened bottle.
"Every order of TestoPrime comes with a zero-hassle, 60-day money-back guarantee. That means if you are not 100% satisfied with your results, then we will return your investment, every single penny, and won’t hold it against you."
TestoPrime's own structured product data lists the same 60-day window, and its page repeats "60-Day Guarantee" more than eight times.
A bottle bought from Testosil can be opened, taken through a full training block, and still come back for a refund, because the seller's window has no end date.
The 300mg has a published study behind it
Testosil's KSM-66 dose matches the per-serving amount used in the trial its own sales page cites.
| The trial behind the KSM-66 dose | |
|---|---|
| Design | Randomized, double-blind, placebo-controlled |
| Participants | 57 men |
| Length | 8 weeks, alongside resistance training |
| Dose used | 300mg KSM-66 per serving, the same per-serving amount in Testosil |
| Published result | Total testosterone up +96.2 ng/dL, against +18.0 ng/dL on placebo (p = 0.004) |
Wankhede et al. 2015. The full Study Card and the citation are in our full Testosil review.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
Pick your Testosil pack
Three packs on Testosil's own store, in US dollars, read Aug 30, 2026. Each bottle holds 120 capsules, a 30-day supply at the label's serving size of 4 capsules.
Every pack carries the same money-back guarantee, with no deadline: return all bottles, opened and unopened, at any time, for a full refund of the purchase price for all unopened bottles and one opened bottle.
Shipping is free to the continental US, per the seller; international shipping shows in the cart before you pay, and the order is a single payment.
Full detail and the study citation: our full Testosil review.
What happens after you click: the page you land on, the single payment, the guarantee
You land on Testosil's own sales page
The hero button opens testosil.com with the full price grid. Each tier button above opens that tier's order page on order.testosil.com with the quantity preset, so the total you see is $69, $177 or $294, in US dollars, on Leading Edge Health's own store.
One-time purchase is the default
Each bottle holds 120 capsules. The order is a single payment; a subscription tab exists on the seller's page and is optional. Shipping is free to the continental US, per the seller, and international shipping shows in the cart before you pay.
The guarantee has no clock
Testosil's money-back guarantee has no deadline: return all bottles, opened and unopened, at any time, and the seller refunds the purchase price of every unopened bottle plus one opened bottle.
Before you order
- Your total is $69, $177 or $294 in US dollars, shown in the cart before you pay; shipping is free to the continental US, per the seller, and international shipping shows in the cart.
- The order is a single payment. A subscription tab exists on the seller's page and is optional.
- The money-back guarantee has no deadline: return all bottles, opened and unopened, at any time, for a full refund of the purchase price for all unopened bottles and one opened bottle.
- Serving size is 4 capsules, with 30 servings per container, as printed on the Supplement Facts panel of the bottle.
- Testosil's own FAQ says to consult a physician first if your symptoms may come from a medical condition, and anyone on hormone, thyroid or other ongoing medication should clear any supplement with a doctor. Nothing on this page is medical advice.
- Prices and guarantee terms were read on each seller's own site on Aug 30, 2026.
The bottle and its label, in the manufacturer's photographs
Both photographs below are Testosil's own. The second one is the Supplement Facts panel printed on the bottle, which is where the 300mg KSM-66 figure comes from.
Photographs taken from the seller's own sales page material.
Who reads this bench
Photos are for illustration.
Every question, answered
How much KSM-66 ashwagandha is in a Testosil serving?
Testosil carries 300mg of KSM-66 ashwagandha per serving, the same per-serving amount used in the published training study behind its formula.
Testosil's own comparison table, read Aug 30, 2026, lists TestoPrime at 55.67mg.
TestoPrime's own site publishes no milligram amount for its ashwagandha, or for any of its 12 ingredients.
How long is Testosil's money-back guarantee?
Testosil's guarantee has no deadline. In the seller's own words it is a 100% satisfaction LIFETIME money-back guarantee: return all bottles, opened and unopened, at any time, for a full refund of the purchase price for all unopened bottles and one opened bottle.
TestoPrime's own site, read the same day, states a 60-day money-back guarantee in its structured product data and repeats 60-Day Guarantee more than eight times across its page.
What does Testosil cost, and does anything renew?
Three packs on Testosil's own store, in US dollars, read Aug 30, 2026: $69 for one bottle, $177 for three bottles at $59 each, and $294 for six bottles at $49 each.
The order is a single payment; a subscription tab exists on the seller's page and is optional. Shipping is free to the continental US, per the seller, and international shipping shows in the cart before you pay.
How do I take Testosil?
The Supplement Facts panel printed on the bottle gives a serving size of 4 capsules, with 30 servings per container; each bottle holds 120 capsules.
Testosil's own FAQ says to consult a physician first if your symptoms may come from a medical condition, and anyone on hormone, thyroid or other ongoing medication should clear any supplement with a doctor. Nothing on this page is medical advice.
Which one should I buy, Testosil or TestoPrime?
Testosil is the pick here: 300mg of KSM-66 per serving, the exact per-serving amount from its published training study, and a money-back guarantee with no deadline.
Testosil's own comparison table puts TestoPrime at 55.67mg of the same extract, and TestoPrime's own site states a 60-day guarantee window.
Where can I read the full Testosil review?
See our full Testosil review for the complete Study Card on the KSM-66 research, all three pricing tiers ($69, $177, $294) and the exact wording of the lifetime guarantee.