Highly recommended
Highly recommended - detail oriented and suspect better guidance than a medical Doctor as it takes into consideration the medications half life and concentration.
By Pam P.
Monday, November 2, 2026 · Customer reviews of US businesses
The Fair Hearing score
Excellent
129 reviews
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Fat Scientist is a free online resource built for people using GLP-1 medications like tirzepatide (Mounjaro, Zepbound) and semaglutide (Ozempic, Wegovy). We specialize in tools and educational content for users of compounded versions of these medications, which come in multi-dose vials and require precise dosage calculations. Our suite of calculators helps users convert prescribed milligram doses into exact syringe units based on their specific vial concentration, calculate split doses for improved tolerability, estimate medication costs, and plan their treatment timelines. Every calculator is free, requires no account, and works on any device. We built Fat Scientist because compounded GLP-1 medications present a unique challenge. Unlike brand-name auto-injectors with pre-measured doses, compounded vials require users to do math that directly impacts their safety. A wrong calculation means injecting too much or too little medication. We believe nobody should have to guess when it comes to their health, and the tools to get it right should be accessible to everyone. Beyond calculators, Fat Scientist provides guides on topics like reading vial labels, understanding concentration values, proper injection technique, and navigating the differences between brand-name and compounded medications. Our FAQ library addresses the most common questions we see in GLP-1 communities, written in plain language without medical jargon. Fat Scientist is operated by Productist LLC. We are not a pharmacy, we do not sell medications, and we are not a substitute for medical advice. Our mission is purely informational — giving GLP-1 users the tools and knowledge to use their medications safely and confidently. We are funded by voluntary donations from our users, not advertising or affiliate deals, so our recommendations are never influenced by commercial interests. Whether you are just starting your GLP-1 journey or adjusting an existing regimen, Fat Scientist is here to help you get the nu
Fat Scientist (fatscientist.com) has 129 customer reviews on The Fair Hearing, with an average rating of 5.0 out of 5.
129 approved reviews, newest moderated first
Highly recommended - detail oriented and suspect better guidance than a medical Doctor as it takes into consideration the medications half life and concentration.
By Pam P.
Very good to to use
By Kim
This website is great. It helps verify the correct dose.
By Eduardo V.
Fat Scientist is an absolute must for anyone using a GLP-1! What a treasure trove of FAQ's and calculators in plain common laymen terminology. I'm now confident in what I'm doing and highly recommend it. This is not some commercial company deal so please support the author with a donation.
By Kevin N.
Response from Fat Scientist· Oct 1, 2026
Thank you so so much! And yes, it's just me, and I do it to help the community. Appreciate the kind words.
Great tool to double check medication doses. Love it! ❤️
By Satisfied U.
Response from Fat Scientist· Oct 1, 2026
Thank you for the kind words!
Super easy to use. Just plug in the numbers, and you get an easy to read diagram. Plus the app is free, with an option for a donation.
By John L.
Response from Fat Scientist· Oct 1, 2026
Thanks John!
I love Fat Scientist!, use it all the time!! I am a GLP-1 patient and also have occasionally reconstituted peptides for injection. Fat Scientist has all the tools that I need to correctly navigate and control my peptide use. Besides all the conversion tools, it is stuffed with informative articles. I realize that most of what this site provides, almost each function can be found through Google-like searches; but why waste your time, when Fat Scientist has it all in one place? I have also found, over the last 8 months, that the site is updated and stays current. I highly recommend keeping a shortcut on your phone/computer if you are GLP-1/peptide user.
By Sharon G.
Just wish I had found you sooner! Amazing information and very helpful tools for anyone starting or already on a GLP-1 treatment.
By Mary