A free peptide research hub

What PepGuru is

PepGuru is a free peptide research hub: reconstitution and unit calculators, plain-English guides, and sourcing references in one place. It exists to answer the practical measurement questions researchers actually have — how much water, how many units, how do I read a certificate of analysis — without the noise that surrounds this subject everywhere else.

Everything here is educational and framed for laboratory research. PepGuru does not sell products, does not fulfil orders, and does not give medical advice.

What the calculators actually compute

There is no black box. Every reconstitution tool performs the same three pieces of arithmetic: concentration equals the amount in the vial divided by the bacteriostatic water added; draw volume equals your target amount divided by that concentration; and syringe units equal the draw volume multiplied by 100, because a U-100 insulin syringe holds 100 units per millilitre.

We show the intermediate numbers deliberately so you can check the result by hand. Blend calculators extend the same maths per component, since every draw from a multi-peptide vial delivers all components in fixed proportion.

What the tools never do is tell you what amount to use. They convert numbers you supply into a measurement you can read on a barrel. That distinction is the whole design.

How we decide what to publish

Reconstitution maths is universal arithmetic and we verify it against worked examples. Handling, storage and quality topics stick to well-established fundamentals that a reader can check independently.

Where a topic would require us to recommend an amount, a frequency or a protocol, we stop. For most compounds in this space no published human dosing regimen exists — which means any protocol circulating online was extrapolated from animal studies or hardened out of forum consensus. Rather than repeat that, we publish an honest evidence ranking showing which compounds actually have human trial data and which do not.

When we do not know something, the page says so. Several supplier reviews carry an explicit list of what we have not been able to verify.

How the supplier rankings work

The tier board weights four signals: independent third-party testing with readable batch COAs, transparency of labelling and policies, consistency across batches, and catalogue depth. Independent lab results always outrank in-house claims.

Tiers are not permanent. A vendor that stops publishing current COAs drops; one that adds independent testing rises. Documentation that contradicts a placement is exactly the sort of evidence that changes it.

Where a vendor has been listed but we lack first-hand data, it appears on the board with its tier and code but no review page. Listing a supplier is a factual claim; reviewing one we know nothing about would not be.

How PepGuru is funded, and what that does not buy

Some supplier links are affiliate links and may earn us a commission, and we accept clearly labelled sponsored placements from vendors. That is how a free site with no paywall and no signup pays for itself.

What that money does not buy is a tier, a favourable review, or removal of an unflattering assessment. The scoring criteria above are applied identically to every vendor, competitors are listed alongside our top pick, and a paying partner that stops publishing batch documentation drops like anyone else. The rankings only have value to a reader — and therefore to a vendor — if that line holds.

The calculators and guides are free and complete on their own. You are never required to buy anything to use them.

Research-use-only, always

Every compound referenced on PepGuru is a research chemical, not an approved medicine. Nothing here is intended to diagnose, treat, cure or prevent any disease, and none of it is medical advice.

Where a compound has an approved pharmaceutical counterpart, that approval attaches to the finished medicine for a specific indication — it does not transfer to research-grade material sold as a reagent. We are careful to state that distinction rather than blur it.

Legality and permitted use vary by jurisdiction and change over time. Confirming what applies where you are is the reader's responsibility, and our regulatory explainer covers the general framing.

Who this is for

People who need the arithmetic right: researchers planning measurements, anyone trying to convert a reference into a syringe reading, and readers who want to evaluate a certificate of analysis rather than take a supplier's word for it.

If you are looking for someone to tell you what to take, this is deliberately the wrong site.

Corrections

If something here is wrong — a number that does not compute, a supplier detail that has changed, a claim that overstates the evidence — we would rather know. Corrections to measurement errors are treated as urgent, because a wrong figure in a calculator is worse than no calculator at all.