Start with the two numbers that define this market. Among the ten highest-scored semaglutide vendors in our index, published pricing runs from $1.00 to $28.33 per milligram, a 28-fold spread for the same molecule. And several of those top-scored names last published a test in the spring of 2025, more than a year ago. PeptideCensus tracks 73 vendors selling semaglutide against 378 published third-party tests, with the newest result from 6 Oct 2026. Compare that to tirzepatide’s 2,813 tests and you see the problem: this is a thin record with old spots, and it rewards careful reading.
Because the approved product got easier to get, compounding absorbed demand until mid-2025, and the weekly doses involved are tiny. In order: With Novo’s direct self-pay pricing bringing Wegovy into the hundreds per month and periodic cuts since. Compounding covered the rest until the FDA’s wind-down deadlines passed in April and May 2025. And a weekly maintenance dose is a fraction of tirzepatide’s milligrams, which weakens the per-mg price argument that drives people to research vendors in the first place. What remains skews toward bulk buyers, which is what the price spread is telling you: the $1 per mg listings are bulk-oriented operations, the $28 listings are US retail storefronts, and both can hold high scores.
Ozempic and Rybelsus (type 2 diabetes) and Wegovy (weight management, approved June 2021, 14.9% mean reduction at 68 weeks in STEP 1) are the approved versions. Compounded semaglutide is finished: 503A pharmacies had until April 22, 2025 and 503B facilities until May 22, 2025. One hazard is specific to this compound: counterfeit Ozempic pens have turned up in legitimate supply chains, which the FDA first warned about in December 2023. That leads to the one hard rule we would state for this market in particular: a research-chemical vendor selling “pens” or pre-filled injectors is a walk-away signal, every time. Legitimate research material ships as lyophilized powder in vials.
Our score already discounts thin records, but no score can make an old test young. The current semaglutide leaderboard makes the point: the top-scored vendor holds an 83 on ten published tests, the last from March 2025. Meanwhile vendors further down the table carry results from June, July, and August 2026. A fifteen-month-old test describes batches that sold out long ago, so for this compound we would treat recency as a filter before rank: find the rows with 2026 dates, then compare scores among those. Check the last-tested column before the score column; each figure links to its source test.
Not legally. The FDA’s deadlines passed in April and May 2025 after the shortage was declared resolved that February. Anyone still offering it is operating outside that framework.
Market positioning. Bulk-oriented sellers price near raw-material cost, US retail storefronts price for small orders and convenience. The same purity can sit at both ends, which is why we publish the per-mg number next to every score.
Buying it for research occupies the same unregulated territory as every other peptide here. The sharper line since 2025 is on the seller side: with compounding over, anyone marketing semaglutide for human use is squarely in warning-letter territory.
The index refreshes daily and the newest semaglutide result is from August 2026, but per-vendor freshness varies enormously, which is the central caution of this guide. Check each vendor’s last-tested date on the semaglutide page.
We rank data, not decisions. But the records differ: tirzepatide has seven times the published tests and much fresher coverage. Our tirzepatide guide covers that market.
Filter the leaderboard by 2026 test dates, compare per-mg price on tested content, and confirm the batch COA verifies. The calculator handles the reconstitution math from there. Canadian buyers face a different vendor pool and customs picture; the Canada guide covers both.
PeptideCensus Editorial is the research team behind the independent peptide lab-result index. Every article is built from published third-party data - trial publications, lab reports, and regulatory records - with every number linked to its source. We don't test, we don't sell, and commissions never touch scores or rankings.
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