What's New on PeptideChat: Calculator, Glossary, Comparisons

PeptideChat started as two things: a chat assistant and a reference library of peptide pages backed by PubMed citations. Over the past few releases we have added a set of tools around that core. None of them change what the site is for. They exist because the same questions kept coming up, and because an answer is only useful if you can check it.

This post walks through what is new, what each tool does, and, just as important, what each one does not do.

The reconstitution calculator

The peptide calculator is free and needs no account. You enter three numbers you already have:

• the amount of peptide in the vial, in milligrams
• the volume of water you add, in millilitres
• the dose you are working with, in micrograms

It returns the concentration, how many micrograms are in each unit on a U-100 insulin syringe, how many units correspond to that dose, and how many doses the vial holds.

A worked example: a 5 mg vial plus 2 mL of water gives 2.5 mg/mL, which is 25 mcg per unit. A 250 mcg dose is then 10 units, and the vial holds 20 such doses.

Why it exists

Reconstitution arithmetic is simple, but it chains three unit conversions together (mg to mcg, mL to units, dose to volume), and each step is a place to slip by a factor of ten or more. That is not a hypothetical concern. In a review of 200 tenfold prescribing errors at a teaching hospital, errors were associated with multiple zeroes in the dose, use of calculations to determine the dose, and conversions between units of measure (Lesar 2002). In an analysis of nursing students' written exams, the most common errors were related to unit conversion (Wennberg-Capellades 2022). If trained people get tripped up, a calculator that shows every intermediate number is worth having.

What it does not do

The calculator converts a dose you already have. It does not recommend one, and it has no opinion about whether any dose is appropriate. That boundary is deliberate and it will not change.

The printable toolkit

The calculator page also offers a free printable toolkit, a cheat sheet and a 4-week dose log, in exchange for an email address. It is the same arithmetic in paper form, for people who prefer to keep records offline.

For the concepts behind the numbers, see the glossary entries on reconstitution and the U-100 insulin syringe.

A 55-term glossary

Peptide research has a vocabulary problem. Words like half-life, agonist, preclinical, and research chemical carry precise meanings, and the difference between them matters when you are judging how much to trust a claim.

The glossary now holds about 55 plain-language definitions, each with its own anchor so it can be linked directly. Because every term has an anchor, an article can point you straight to a definition, as this one does, so you can check a word without losing your place.

Why it exists

An evidence-first site that uses jargon without explaining it is only evidence-first for readers who already know the field. Defining terms once, in one place, keeps explanations consistent across the whole site.

17 side-by-side comparisons

Many questions arrive as "X or Y?": BPC-157 vs TB-500, semaglutide vs tirzepatide, CJC-1295 vs ipamorelin, Semax vs Selank. The compare section now has 17 of these, laid out side by side.

Why it exists

Two compounds are often discussed as if they were interchangeable when the evidence behind them is very different. One may have randomized trials in humans and the other only animal data. Putting them next to each other makes that gap visible, which is often the most useful thing a comparison can show. A comparison is not a ranking and not a recommendation; it is a way to see the evidence for each compound at the same resolution.

A redesigned My Schedule

My Schedule is available with a free account. It is a personal record-keeping tool, and it was rebuilt around how people actually use it day to day:

• Today view with check-offs. A checklist of what is on your schedule today, where you can mark each item as done.
• Weekly grid. The whole week at a glance, which also prints as a grid.
• Units to draw. Each item can carry the calculator's result, so the number of units on a U-100 syringe is shown alongside the entry.
• Phone reminders. You can export your schedule as a calendar (.ics) file and let your phone's calendar handle reminders.

Why it exists

Record-keeping is not glamorous, but a written log is how you notice what you actually did rather than what you meant to do. My Schedule records what you enter; it does not suggest doses, timing, or combinations.

"Last updated" dates on peptide pages

Every peptide page, such as BPC-157, now shows a "Last updated" date. Each page lists research status (Clinical, Preclinical, or Research chemical), mechanism, reported dosing from studies (not recommendations), side effects, and PubMed-verified studies.

Why it exists

Research moves. A summary that was accurate two years ago may miss a trial that changed the picture. A visible date lets you judge how current a page is instead of assuming it is.

The methodology and disclosure page

The methodology page explains how we work:

• how citations are verified against PubMed before they appear on the site
• what the research labels (Clinical, Preclinical, Research chemical) mean
• our affiliate disclosure, so you know how the site is funded

Why it exists

A citation is only as good as the process that put it there. We think readers should be able to see that process, including the parts that involve money. If you find a citation that does not match its source, that page tells you what we check, so you can hold us to it.

What stays the same

The peptide library, stacks, and the chat assistant work as before. The new tools sit around them and share one principle: show your working. Every number the calculator gives you can be checked by hand, every study cited on a peptide page links to its PubMed record, and every comparison shows where the evidence is strong and where it is thin.

If something is unclear or looks wrong, that is useful to us. Accuracy is the product.

Sources

• Tenfold medication dose prescribing errors. Ann Pharmacother, 2002. PMID 12452740
• Where do nursing students make mistakes when calculating drug doses? A retrospective study. BMC Nurs, 2022. PMID 36357884

This article is for educational and research purposes only and is not medical advice.