Most people searching for a BPC-157 dosage calculator are really looking for one number: how many units to draw on their syringe. The irony is that the math itself takes about thirty seconds once you understand it. The real danger is the mg-to-mcg conversion, and almost none of these tools bother to explain why getting it wrong by a factor of 1,000 is a very serious problem. That gap matters. Here is how eight tools stack up.

1. FormBlends Peptide Calculator

The single thing that sets this one apart from every other free tool in this category is that it shows you the actual arithmetic, step by step, rather than just returning a number. You can verify every output yourself. That alone makes it worth bookmarking.

You enter three things: how much peptide is in the vial (mg or mcg), how many mL of bacteriostatic water you added, and your intended dose per injection. The calculator returns the concentration per mL, the exact units to draw, and a visual syringe fill bar showing where that volume sits on the barrel. It handles the mg-to-mcg conversion automatically, which is the most common and most dangerous mistake in peptide prep. Confusing 5 mg with 5 mcg is a 1,000x error.

It defaults to U-100 syringes but also supports U-50 and U-40, which is genuinely rare among free web tools. One-tap presets cover BPC-157 at 5 mg and 10 mg vials, TB-500 at 5 mg, ipamorelin at 10 mg, tesamorelin at 2 mg, and a GLP-1 preset at 50 mg. The same calculator lives inside the FormBlends mobile app alongside a 55-compound library, dose logging, and an injection-site rotation map.

No sign-up. No cost. Built by a company that operates a 503A pharmacy, not an anonymous page with no address.

Best for: Anyone who wants to see the math, not just trust it.

2. PeptideFox

PeptideFox covers more than 30 peptides and is one of the few tools that explicitly thinks about BAC water volume optimization, meaning it nudges you toward volumes that produce clean, whole-number unit draws on standard syringes. That is a practical detail most calculators ignore entirely. It also includes a visual guide explaining the reconstitution process. Solid choice for anyone working with less common compounds beyond BPC-157.

3. PeptideDeck

Simple and direct. You enter the total mg in your vial, the mL of BAC water, and your target dose in mcg. PeptideDeck outputs concentration, draw volume in mL, and the equivalent in insulin syringe units. Nothing fancy. No app, no library. But for BPC-157 specifically, it does exactly what you need in three fields. Good for people who find the busier calculators distracting.

4. MyPeptideMatch

Free tool that covers BPC-157, TB-500, semaglutide, tirzepatide, and several other injectables in one place. Worth mentioning because the GLP-1 coverage is increasingly relevant to people who are also managing weight compounds alongside healing peptides. No sign-up required. The interface is plain, which is either a feature or a flaw depending on your tolerance for minimalism.

5. LeadWest Medical

LeadWest is a medical provider, not just a calculator page, which colors how this tool presents itself. It covers BPC-157, TB-500, ipamorelin, CJC-1295, tesamorelin, sermorelin, retatrutide, and GHK-Cu. The clinical framing means the language around dosing is conservative and provider-oriented, which some people find reassuring and others find frustrating if they just want a number fast.

6. Outliyr

Outliyr covers a similar compound list: BPC-157, TB-500, ipamorelin, CJC-1295, tesamorelin, GHK-Cu, and the GLP-1 class. The site has a biohacking editorial bent, so the calculator sits inside a broader content environment with context about what each peptide is and why dosing precision matters. Useful if you are new to reconstitution and want some surrounding explanation rather than a bare-bones widget.

7. peptidereconstitutecalculator.com

This one is BPC-157-specific, no other compounds. It handles the mcg-to-units conversion for U-100 syringes and nothing else. Narrow scope, but if BPC-157 is your only concern and you want a single-purpose page with no distractions, it works. The anonymous nature of the site means there is no company to contact if something seems off, so double-check outputs against the manual math (total mcg in vial divided by mL added = mcg per mL, then divide target mcg by that number, then multiply by 100 for U-100 units).

8. peptides.org Dosage Charts

Not an interactive calculator. Static reference charts showing common dosing ranges and reconstitution examples. The value here is context, not calculation. Useful for sanity-checking whether your intended dose falls within typically reported ranges before you run the numbers elsewhere. Not a replacement for a real calculator, but a reasonable secondary reference.

Quick Comparison

Tool	BPC-157	Multi-Peptide	Shows Math	App Available	Free
FormBlends Peptide Calculator	Yes	Yes	Yes	Yes (iOS/Android)	Yes
PeptideFox	Yes	Yes (30+)	Partial	No	Yes
PeptideDeck	Yes	Yes	No	No	Yes
MyPeptideMatch	Yes	Yes	No	No	Yes
LeadWest Medical	Yes	Yes	No	No	Yes
Outliyr	Yes	Yes	No	No	Yes
peptidereconstitutecalculator.com	Yes	No	No	No	Yes
peptides.org Charts	Reference only	Yes	N/A	No	Yes

FAQ

Why does adding more BAC water change the units I draw but not the total dose?

Because the peptide mass is fixed. A 5 mg vial contains 5 mg no matter how much water you add. More water means lower concentration per mL, so you draw more volume to hit the same dose. The dose itself does not change.

What is the most dangerous math mistake in peptide prep?

Confusing mg and mcg. One milligram equals 1,000 micrograms. If your target dose is 250 mcg and you accidentally dose 250 mg, that is a 1,000-fold overdose. Always confirm which unit the calculator is using and which unit your provider prescribed.

Do all these calculators work for peptides other than BPC-157?

The reconstitution math is identical for any lyophilized peptide. Tools that support multiple compounds are just applying the same formula with different default presets. The only BPC-157-specific tool in this list is peptidereconstitutecalculator.com.

What syringe should I use for BPC-157?

Most people use U-100 insulin syringes (100 units per 1 mL). At a typical 250 mcg dose reconstituted in 2 mL BAC water, you would draw around 10 units. U-50 syringes (50 units per 0.5 mL) are also common and can make small draws easier to read.

Are any of these tools prescribing a dose?

No. Every calculator here requires you to enter your own target dose. They only tell you how to measure it accurately on a syringe. Determining the right dose for your situation is a conversation for a qualified prescribing provider, not a web form.

A note before you use any of these: calculator outputs are only as good as the inputs you enter, and none of these tools replace a prescription or clinical guidance. If you are working with a compounding pharmacy or telehealth provider, confirm your reconstitution plan with them directly.

Sources

• U-100 syringe unit-to-volume conversions: standard insulin syringe labeling and FDA device documentation
• peptides.org: publicly accessible dosage reference charts
• PeptideFox feature descriptions: peptidefox.com product page (verified 2025)
• MyPeptideMatch, LeadWest Medical, Outliyr, PeptideDeck, peptidereconstitutecalculator.com: publicly accessible web tools, reviewed directly
• FormBlends Peptide Calculator: FormBlends web tool and app store listings (iOS/Android, verified 2025)