Peptide comparison engine
Line up vendor offers, price per mg, ratings and availability without leaving the platform. Sorted by price per mg, so the cheapest vial and the cheapest milligram stop being confused.
Independent peptide research platform
Peptide research.
Finally organized.
Peptide Library is an independent peptide research platform. Calculate concentrations, track every dose and vial, and compare vendors across 208 peptides — from one place. It does not sell peptides.
Free, in your browser, no account needed.
Research platform onlyPeptide Library does not sell peptidesBuilt for research use only. Not for human consumption.
Retatrutide
33 vendors
$5.48–$7.07/mg
GHK-Cu (Copper Peptide)
46 vendors
$0.517–$0.855/mg
What is Peptide Library?
Peptide Library is an independent platform for researching peptides, comparing vendors and pricing, calculating concentrations, and tracking research. It does not sell peptides. Content is for research and educational use only and is not medical advice.
- Peptide profilesSearchable research records
- 208
- VendorsListed independently
- 50
- Average vendor ratingWeighted by review count
- 5.0
Everything in one research workflow.
One platform.
Every part of the workflow.
Search, compare, calculate, track — the whole sequence in one place, instead of four tools and a spreadsheet.
Search
One searchable library
Search 208 peptide profiles by name, alias, molecular data or reference, from a single field.
Compare
Every offer, side by side
Vendor offers ranked by price per mg, with rating and availability, so the cheapest vial and the cheapest milligram stop being confused.
Calculate
Concentrations in one flow
Vial amount, diluent volume and target dose resolve to a calculated volume without leaving the screen.
Track
The part after the maths
Schedules, logs, inventory, notes and metrics on one timeline, so a protocol stays consistent over months rather than tabs.
01 / Search
208 profiles.
One searchable library.
Structured peptide profiles with research information, identifiers, references, regulatory context and vendor comparison.
Or browse the full library by category.
02 / Compare
Compare the market.
Not just the sticker price.
See vendor pricing, price per mg, ratings, and availability in one place. A cheaper vial is not a cheaper milligram.
Live offers for DSIP. Select a column heading to sort.
Compare every peptide →| Vial | Availability | ||||
|---|---|---|---|---|---|
| Royal PeptidesBest $/mg | 10mg | $350.00 | $3.50 | No reviews | In stock |
| Amino Club | 15mg | $59.99 | $4.00 | 5.0 (1) | In stock |
| ModFit Supps | 2mg | $80.00 | $4.00 | No reviews | In stock |
| Atomik Labz | 10mg | $405.00 | $4.05 | No reviews | In stock |
| Solution Peptides | 10mg | $405.00 | $4.05 | No reviews | In stock |
| Particle Peptides | 10mg | EUR 40.64 | $4.06 | No reviews | In stock |
| Premier Research | 15mg | $63.75 | $4.25 | No reviews | In stock |
| Peptide Titans | 10mg | $44.99 | $4.50 | 5.0 (10) | Out of stock |
Sorted by price per mg, lowest first. Not a paid advertising ranking — coupons or affiliate links do not change the order. How rankings work
03 / Calculate
The maths, done once.
Reconstitution, dosing and blends in one flow — free, in the browser, no account needed. Every peptide profile opens it with that compound’s typical vial size already filled in.
- Reconstitution
- Enter the vial size and the bacteriostatic water you add. Returns the concentration in mg/mL.
- Dosing
- Enter a dose in micrograms. Returns the volume to draw, the units on a U-100 insulin syringe, and how many doses the vial holds.
- Blends
- Put two or more peptides in one vial and see each concentration at a shared water volume.
Example calculation
- Vial
- 5 mg
- Bacteriostatic water
- 2 mL
- Concentration
- 2.5 mg/mL
- Volume drawn
- 0.10 mL
- Amount
- 250 mcg
- On a U-100 syringe
- 10 units
An illustration of the arithmetic, not a dose recommendation. Research use only.
04 / Track
Research doesn’t stop at the calculation.
Schedules, logs, metrics, notes and inventory on one timeline, so a protocol stays consistent over months instead of living in a spreadsheet and a camera roll.
- Schedules
- What is due, and when.
- Logs
- Every entry, dated, in one timeline.
- Metrics
- Weight, body fat and your own measures over time.
- Journal
- Free-text notes against the day they belong to.
- Inventory
- Remaining amounts and stock, per vial.
- Reminders
- So a protocol survives a busy week.
Tracking and inventory live behind a free account, and sync across devices with Pro.
Built for serious research.
Research tracker
Schedules, logs, reminders and metrics on one timeline.
Guided courses
Step-by-step lessons from the fundamentals up, with your progress saved as you go.
Peptide calculator
Concentrations, units and injection volume from a single flow.
208
Peptide profiles
Searchable research records, not a static list.
50
Vendors
Listed independently, with ratings and review counts.
Inventory management
Remaining amounts, stock levels and reorder context, so nothing runs out mid-protocol.
Cloud sync with Pro
Keep tracker and inventory in step across devices with secure cloud backup.
Methodology
Know where the data comes from.
Every profile is assembled from published literature and public registries, cited against its source and dated when it was last reviewed.
01
Published research
Profiles are built from peer-reviewed literature, with citations recorded against PubMed identifiers and DOIs rather than summarised second-hand.
- PubMed
- DOI
- Peer-reviewed
02
Regulatory and registry data
Chemical identity and regulatory context come from public chemical registries and regulator records, so identifiers can be checked against their source.
- PubChem
- ChEMBL
- CAS
- UNII
03
Verified references
Citations are audited, profiles carry a review date, and corrections are versioned — so a profile states when it was last checked, not just what it says.
- Citation audit
- Review dates
- Versioning
Read the full methodology →Editorial policy →How rankings work →
What researchers are exploring.
The peptides drawing the most attention on the platform right now, with vendor counts and the typical price per mg.
Retatrutide
33 vendors
$5.48–$7.07/mg
View offers →
GHK-Cu (Copper Peptide)
46 vendors
$0.517–$0.855/mg
View offers →
MOTS-C
44 vendors
$3.50–$4.80/mg
View offers →
Tirzepatide
30 vendors
$3.70–$5.70/mg
View offers →
5-Amino-1MQ
39 vendors
$1.18–$4.37/mg
View offers →
KLOW (GHK-Cu / KPV / BPC-157 / TB-500)
43 vendors
$1.23–$1.75/mg
View offers →
Research Intelligence Center
Peptide research, measured.
Original statistics on the published science behind every peptide in the library: PubMed publications and ClinicalTrials.gov registrations, classified by study type and evidence, counted the same way every time and free to cite.
- Peptide publications analyzed
- 63,998
- Share of publications that are human clinical research
- 37.8%
- Registered clinical trials
- 4,796
Report edition 2026.1 · data through September 30, 2026 · version 2026.1
State of Peptide Research 2026
The annual report on how peptide research has grown and where human evidence is thin.
Research dashboard
Filter publications and trials by peptide, research area, study type and evidence class.
Research by peptide
Publication and trial counts for every indexed peptide.
Datasets
Download the data behind every chart as CSV, JSON or XLSX, licensed CC BY 4.0.
Open the Research Intelligence Center →How it is counted →Press and media →
Peptide Library.
In your pocket.
Track research, calculate concentrations, manage inventory, compare vendors, and explore the library anywhere.
Over 20,000 downloads across the App Store and Google Play.
Calculator
Tracker
Inventory
Start free. Go Pro when you need more.
Comparison, vendors, and the library stay free. Pro unlocks sync, unlimited inventory, and advanced tools in the app.
Free
$0
Research, compare, and calculate on the web.
- Browse the peptide library
- Compare vendor offers and $/mg
- Vendor ratings and review counts
- Single-peptide calculator
- Inventory for 1 peptide
- Up to 2 containers per item
Peptide Library Pro
$4.99 / month
$39.99 yearly or $89.99 lifetime.
- Unlimited inventory
- Cloud sync and backup
- Blend calculator
- Courses and community Q&A
- Data export and advanced tracking
- Progress photos and research dashboard
Get Pro in the app
Subscriptions are purchased and managed in the mobile apps.
Work with us
Vendors, creators, developers and press.
Get your store listed, earn by sharing Peptide Library with your audience, build on our data, or cite our research.
Vendors
List your store
Apply to be listed in the vendor directory and price comparison. Listing is free and ranking never depends on payment. Listed vendors reply to reviews and propose listing updates in the vendor portal.
Creators
Creator Partner Program
For research, longevity, fitness and wellness creators. Share your link and code, and earn a share of every Pro subscription you bring, renewals included.
Developers
API and AI assistants
Build on the library with the public REST API (peptide profiles, research statistics and, with a key, vendor prices) and connect AI assistants through the MCP server.
Press
Journalists and researchers
Cite the Research Intelligence Center: approved statistics, charts to embed, datasets, ready-made citations and a media contact.
Questions.
Answered.
“Pinning” is informal slang for administering a substance with a needle and syringe. In peptide discussions it almost always means a subcutaneous or intramuscular injection, as opposed to an oral, nasal, or topical route.
The term comes from community forums rather than clinical literature — it will not appear in a published study or on a product label. It describes only the act of injecting, and carries no information about what is being administered, at what dose, or for what purpose.
Related terms you will see alongside it
- Subq / sub-Q / SC — subcutaneous, into the fat layer beneath the skin. See What is subcutaneous administration?
- IM — intramuscular, into muscle tissue. See What is intramuscular administration?
- Slin pin — an insulin syringe, typically U-100, graduated in units rather than millilitres
- Gauge — needle thickness, where a higher gauge number means a thinner needle
- Recon / reconstitute — dissolving a freeze-dried powder into liquid before it can be drawn. See What does “reconstitution” mean?
- BAC water — bacteriostatic water, the diluent most often used for reconstitution
Why the route comes up so often
Most peptides are not orally active: stomach acid and digestive enzymes break the peptide bonds before absorption, which is why injection dominates the discussion. Why are most peptides not orally active? explains the mechanism.
A dose is expressed as a mass in milligrams or micrograms but drawn as a volume, and the two are linked by the concentration of the reconstituted vial. The reconstitution calculator converts between them.
Peptide Library documents this terminology for research literacy. Nothing here is instruction in injection technique, and none of it is medical advice.
Reconstitution is the process of adding a liquid (commonly bacteriostatic water) to a lyophilized (freeze-dried) peptide powder to prepare it for research use.
Peptides are shipped as dry powder for stability and must be reconstituted before use.
Yes. Your tracker, metrics, and journal data are private to your account and are not shared publicly.
GLP-1 receptor agonists are compounds that activate the GLP-1 (glucagon-like peptide-1) receptor, which is involved in glucose regulation and appetite signalling.
In research literature, GLP-1 activity is associated with:
- Increased glucose-dependent insulin secretion
- Reduced glucagon secretion, context-dependent
- Slower gastric emptying
- Changes in appetite and satiety signalling
Why "agonist" and not "GLP-1"
Native GLP-1 is useless as a drug: DPP-4 degrades it within roughly two minutes of release. Every clinically useful compound in this class is therefore an analog engineered to survive that enzyme — and often to bind albumin as well, pushing the half-life from minutes to days.
That engineering is what separates the generations. Early agonists required twice-daily administration; later ones with albumin-binding modifications moved to weekly.
Glucose-dependent is the key phrase
The insulin effect scales with blood glucose rather than firing regardless of it. That dependency is why the mechanism behaves differently from insulin itself.
Beyond GLP-1 alone
Newer compounds add other receptors — GIP, or GIP plus glucagon. See how the three receptors differ and the GLP-1 and metabolic category.
Research use only. Not medical advice.
Peptides can degrade over time. “Expiration” typically refers to the point where a compound may no longer meet a stated purity or stability expectation.
Researchers often track:
- Lot/batch identifiers
- Storage conditions (temperature, light, moisture)
- Dates and documentation (COAs)
Always follow vendor guidance and lab best practices.
Vendor ratings are based on:
- User reviews
- Verified purchase submissions (when available)
- Transparency indicators (COAs, lab reports)
- Shipping reliability
- Community feedback
Peptide Library may use a combination of:
- Publicly available vendor listings
- Automated collection where permitted
- Manual verification and user-submitted corrections
Because vendor catalogs change frequently, always confirm final details on the vendor’s website.
Price per mg is calculated using:
Total Price ÷ Total Milligrams = $/mg
This allows you to objectively compare different vial sizes, blends, and vendors on equal footing.
One research platform
Research smarter.
Stay organized.
Everything you need for peptide research in one platform.
Peptide Library is an independent research platform and does not sell peptides. Content is for research and educational purposes only and is not medical advice.