Research peptides, reviewed properly.

Every guide on this site is built from peer-reviewed literature and clinical trial data — not forum folklore. Start with the free dosage calculator, then read the review before you buy anything.

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The guides our readers use most.

Tool

Peptide Dosage Calculator

Reconstitution math done for you: mg per vial, water added, and exactly how many units to draw on a U-100 syringe.

Retatrutide

Retatrutide: Complete Guide

The triple agonist with the largest weight-loss results yet reported — and no approval. Phase 3 data, dosing, cost, access.

Retatrutide

Retatrutide Dosage Guide

Trial titration schedules with a week-by-week chart, plus the 6 mg step that was never actually in a trial.

Retatrutide

Where to Buy Retatrutide

How to vet a research supplier: COAs, HPLC and MS testing, purity claims, and red flags to avoid.

Buying guide

Best Peptides for Weight Loss

GLP-1s, GIP co-agonists, and the compounds that actually have trial data behind them — ranked.

Buying guide

Best Peptides for Fat Loss

Which compounds have body-composition data, and which fat burners failed their human trials.

Buying guide

Where to Buy Peptides

Four checks that separate a real supplier from a repackager, plus realistic price ranges.

Buying guide

Best Peptides for Muscle Growth

The honest version: what growth hormone research actually found about lean mass and strength.

Retatrutide

Retatrutide Side Effects

What the Phase 2 trials reported by dose, and why almost every tolerability problem is a titration problem.

Retatrutide

Retatrutide Cost & How to Get It

Trial enrollment, the approval timeline, and real monthly cost by dose versus approved GLP-1s.

PT-141

PT-141 (Bremelanotide)

The melanocortin agonist approved as Vyleesi: trial dosing, onset, and the blood pressure caution.

KPV

KPV Peptide Guide

The α-MSH fragment being studied for gut inflammation and skin repair: mechanism, dosing, safety.

MOTS-c

MOTS-c Peptide Guide

The mitochondrial-derived peptide behind the insulin sensitivity and exercise capacity research.

Growth hormone

CJC-1295 & Ipamorelin

How the pairing works, DAC versus no-DAC, blend vial math, timing rationale and side effects.

Repair

BPC-157 Side Effects & Dosage

The gastric peptide with the deepest animal literature — and the angiogenesis question nobody has settled.

Repair

TB-500 Guide

The thymosin beta-4 fragment: loading protocols, what the parent protein proved, and what it did not.

Safety

Are Peptides Safe?

What the research says about side effects, contamination risk, and why source purity matters most.

How we review

Four things we check before a peptide gets a recommendation.

1. Published evidence

We read the primary literature on PubMed and ClinicalTrials.gov. If human data does not exist, we say so plainly instead of implying it does.

2. Third-party purity data

A certificate of analysis with HPLC and mass-spec results, tied to the batch you actually receive — not a generic PDF from two years ago.

3. Dosing that matches trials

Reference ranges come from published protocols where they exist, converted into practical per-vial math with our calculator.

4. Supplier track record

Shipping reliability, batch consistency, responsiveness, and whether the company stands behind an order when something goes wrong.