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COA checks & dose maths

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Original research

The r/Peptides census

We pulled one trailing year of r/Peptides and r/compoundedtirzepatide, 28,313 posts and 273,921 comments, and counted what the community actually talks about. Retatrutide leads at 15.5% of posts. One post in nine is dose arithmetic. Vendor vetting runs on reputation, not lab evidence. And the pharmacy-compounded sub grew 5.6x while the gray-market sub cooled. Every table below is reproducible from public data.

Data window: 27 August 2025 to 27 August 2026, via the Arctic Shift archive. Counts computed 29 August 2026.

Finding 1

Which compounds does the community actually discuss?

Retatrutide, by a wide margin: 2,613 of 16,878 r/Peptides posts name it, 15.5% and the top of the table. The striking part is the other end. Semaglutide, the most prescribed GLP-1 drug in the world, appears in 1.0% of posts. The sub is not a mirror of the peptide market; it is the help desk for the part of it that has no pharmacist.

0% 5% 10% 15% Retatrutide: 2,613 posts (15.5%) Retatrutide 15.5% GHK-Cu: 1,853 posts (11.0%) GHK-Cu 11.0% BPC-157: 1,515 posts (9.0%) BPC-157 9.0% Ipamorelin: 1,371 posts (8.1%) Ipamorelin 8.1% CJC-1295: 1,314 posts (7.8%) CJC-1295 7.8% GLOW/KLOW blends: 845 posts (5.0%) GLOW/KLOW blends 5.0% TB-500: 843 posts (5.0%) TB-500 5.0% Tirzepatide: 638 posts (3.8%) Tirzepatide 3.8% MOTS-c: 499 posts (3.0%) MOTS-c 3.0% Semaglutide: 167 posts (1.0%) Semaglutide 1.0%
Every count is reproducible from the table below.
Share of r/Peptides posts naming each compound, title plus body, trailing year (n = 16,878)
CompoundPostsShare
Retatrutide2,61315.5%
GHK-Cu1,85311.0%
BPC-1571,5159.0%
Ipamorelin1,3718.1%
CJC-12951,3147.8%
GLOW/KLOW blends8455.0%
TB-5008435.0%
Tirzepatide6383.8%
MOTS-c4993.0%
Semaglutide1671.0%

Document frequency: a post naming three compounds counts once for each. Spelling variants and common abbreviations are folded in. The ranking explains this site's coverage order; the retatrutide calculator and dosage guide exist because this table says they should.

Finding 2

What does the community not understand?

The arithmetic. 1,886 r/Peptides posts, 11.2% or one in nine, land in a dose-maths confusion family: reconstitution, syringe units, or unit conversion. And the two subs are confused about opposite things. r/Peptides asks how to mix powder; the pharmacy sub asks how to read a syringe, because its vials arrive pre-mixed and the mixing problem never happens.

r/Peptidesr/compoundedtirzepatide
0% 2% 4% 6% 8% Reconstitution and BAC water r/Peptides: 7.6% — Reconstitution and BAC water r/compoundedtirzepatide: 0.6% — Reconstitution and BAC water 0.6% 7.6% Units and syringes r/Peptides: 2.2% — Units and syringes r/compoundedtirzepatide: 4.7% — Units and syringes 2.2% 4.7% Dose conversion and calculation r/Peptides: 3.4% — Dose conversion and calculation r/compoundedtirzepatide: 3.4% — Dose conversion and calculation 3.4% / 3.4% "Did I ruin it" r/Peptides: 0.6% — "Did I ruin it" r/compoundedtirzepatide: 0.8% — "Did I ruin it" 0.6% / 0.8% Storage r/Peptides: 2.5% — Storage r/compoundedtirzepatide: 2.3% — Storage 2.3% / 2.5%
The mirror inversion: the sub that mixes powder asks about water; the sub with pre-mixed vials asks about syringes.
Share of posts matching each confusion family, negation-aware regex, trailing year
Familyr/Peptidesr/compoundedtirzepatide
Reconstitution and BAC water7.6%0.6%
Units and syringes2.2%4.7%
Dose conversion and calculation3.4%3.4%
"Did I ruin it"0.6%0.8%
Storage2.5%2.3%
Any of the first four11.2%8.3%

Families overlap, so rows exceed the union. The inversion in the first two rows is the cleanest structural finding in the corpus: gray-market users struggle with mixing, pharmacy users with measuring. A calculator that only does reconstitution serves half the confusion.

Finding 3

Which way is the market moving?

5.6×

growth in r/compoundedtirzepatide comment volume across the year: 8,828 comments in the first 73-day window, 49,336 in the last.

The two subs moved in opposite directions. The pharmacy-compounded sub compounded all year and overtook the general sub in the spring. r/Peptides itself peaked in midwinter at 32,180 comments per window and then fell about 40% by late summer. The audience arriving in this niche is increasingly someone holding a pre-mixed pharmacy vial and an insulin syringe, not a bag of raw powder.

That matches what the keyword data shows from the search side, where dosing and calculator queries grew 4 to 13x year over year. The demand is real, recent, and still forming its habits.

r/Peptidesr/compoundedtirzepatide
0k 10k 20k 30k 40k 50k Aug–Nov '25 Nov–Jan Jan–Apr '26 Apr–Jun Jun–Aug r/Peptides, Aug–Nov '25: 20,767 comments r/Peptides, Nov–Jan: 26,681 comments r/Peptides, Jan–Apr '26: 32,180 comments r/Peptides, Apr–Jun: 24,821 comments r/Peptides, Jun–Aug: 19,392 comments r/Peptides r/compoundedtirzepatide, Aug–Nov '25: 8,828 comments r/compoundedtirzepatide, Nov–Jan: 15,999 comments r/compoundedtirzepatide, Jan–Apr '26: 30,125 comments r/compoundedtirzepatide, Apr–Jun: 45,792 comments r/compoundedtirzepatide, Jun–Aug: 49,336 comments r/compoundedtirzepatide
The crossover, spring 2026: the pharmacy-compounded sub overtakes the general one.
Comments per 73-day window, both subreddits, 27 August 2025 to 27 August 2026
Windowr/Peptidesr/compoundedtirzepatide
Aug to Nov 202520,7678,828
Nov 2025 to Jan 202626,68115,999
Jan to Apr 202632,18030,125
Apr to Jun 202624,82145,792
Jun to Aug 202619,39249,336

Finding 4

How does the community vet vendors?

492 vs 76

r/Peptides posts using legit-or-scam vetting language against posts naming Janoshik, the lab whose reports the whole market's trust runs through.

By asking strangers. 492 posts, 2.9% of the year, use legit-or-scam language about a seller. Far fewer reach for evidence: 112 posts mention a COA or test report, 108 mention purity, 76 name Janoshik, 62 say third-party tested. Reputation questions outnumber every category of lab evidence by roughly four to one.

The infrastructure for evidence exists. The lab runs a free verification form, keeps a public archive, and sellers attach reports to listings. The reflex just has not caught up with the tooling, which is the gap this site exists in: a report you have not verified is a screenshot, and a thread of strangers saying "legit" is weaker than either.

The receipts

Three threads that carry the whole story.

Aggregate counts flatten things. These threads, cited by id, are what the numbers look like up close.

The units problem

The year's loudest dose-maths thread (score 281, 113 replies) is titled "PLEASE STOP USING UNITS TO MEASURE YOUR DOSE". Its argument is the arithmetic this site's calculators print: units describe volume, so two identical 30 mg vials give different doses per unit once different amounts of water go in. Dose lives in milligrams; the syringe reading is derived. Thread 1thoyou.

The blend problem

A user on an 80 mg four-compound KLOW blend in 3 mL could not say how much GHK-Cu a 20-unit draw carried. The top correction worked it out: 3.3 mg, plus roughly 667 mcg of each other component, in every draw, at a ratio the vial fixed. The arithmetic is on our blend page; the thread is 1sm1t98.

The demand signal

Two community-built calculators launched inside the year to warm receptions: a comparison database (score 176) and a solve-backwards calculator whose pitch was that existing tools ask the wrong question (score 86). Threads 1qknmko and 1quss9h. The confusion census above is the demand those builders saw.

Use these numbers

Cite anything on this page with a link to it. The dataset is public Reddit data via the Arctic Shift archive; the counts are document-frequency regex matches over titles, bodies and comments, and the method section below is enough to reproduce every table.

Method and limits

How the counting worked.

One trailing year, 27 August 2025 to 27 August 2026, of r/Peptides (16,878 posts, 123,841 comments) and r/compoundedtirzepatide (11,435 posts, 150,080 comments), pulled from the Arctic Shift archive of public Reddit data. Compound counts are regex document frequency over post title plus body, with spelling variants folded in. Confusion families use the same patterns with a negation window, so "no bac water needed" does not count as a reconstitution question.

The limits are the usual ones. Counts are documents, not people. Subreddits are self-selected, so these numbers describe the communities, not the market; deleted posts are counted where the archive holds them and lost where it does not. Comment-volume windows follow the archive's 73-day scrape chunks. No language model classified anything: every number is a pattern match you can rerun.

Sources

Arctic Shift archive  //  r/Peptides  //  r/compoundedtirzepatide  //  MechPeptides archive mirror

Published 29 August 2026. Quoted thread titles and figures belong to their authors; threads are cited by id. Educational content; research compounds are not for human consumption.

Scope

What this study is

MechPeptides sells nothing. This page counts public forum discussion of research compounds; it does not evaluate any compound, endorse any practice the counts describe, or offer medical advice.

Popularity is not evidence. The table-topping compound in finding 1 has no approved product anywhere, and the doses the community names most often have never been tested in a human dose-finding study.