About FreePeptideCalc

FreePeptideCalc is a free reconstitution and dosage calculator covering 33 compounds, built against 205 primary sources.

Why build another one

There are plenty of peptide calculators. The arithmetic is simple enough that most of them get it right. What almost none of them do is tell you where their dosing information came from — dose ranges, half-lives and discard windows appear as bare assertions, and tracing them usually dead-ends at another site that also cited nothing.

That gap is the reason this site exists. Every figure here links to the FDA label or the published study it came from, and where nothing reliable has been published, the page says so rather than filling the space.

What is different

• Sourced dosing. Every number traces to a named document you can open.
• Approved and unapproved are never presented alike. An FDA-labelled drug and an unapproved research chemical get visibly different treatment.
• Reverse solving. Most calculators only go forward from a water volume. This one also answers the question people actually have: how much water do I add so my dose lands on a readable number of units.
• A real syringe. Drawn to scale with correct gradations, and redrawn for U-40 and U-500 barrels instead of assuming everything is U-100.
• A calendar, not just a dose count. It shows whether your discard date arrives before you finish the vial, and how many doses that wastes.
• Nothing gated. The dosing charts print straight to PDF. No email, no account, no download form.

How a number gets onto this site

The process is deliberately mechanical, because judgement applied case by case is how sites in this niche end up publishing numbers nobody can trace.

1. Find the primary document. An FDA label, a regulator decision, a published trial, a pharmacopoeial standard. Not another calculator, not a clinic’s blog, not a vendor’s product page.
2. Register it. The document goes into a citation registry with its title, publisher, URL and the date of the document itself — not the date we read it.
3. Attach the id to the figure. Dosing figures carry the id of the source they came from. A figure with no id does not render as a figure.
4. Where there is no document, publish the gap. This is the step that makes the rest work. “No reliable source found” is a finding, and on several pages here it is the most useful sentence on them.

The consequence is visible on the thinnest pages. The sermorelin page reproduces no reconstitution volume because the FDA does not host the withdrawn label and no primary source for one exists. The Vesugen page publishes no milligrams-per-day figure because no controlled trial has established one. Both pages would be longer if we were willing to repeat what vendors say. Neither would be more true.

What is actually tested

The arithmetic is covered by runnable check suites rather than by assertion — concentration and draw volume, unit conversion across U-40, U-100 and U-500 scales, vial depletion against discard dates, cost per usable dose, the weight-projection model and the accumulation plotter. They run as one command and have to pass before anything ships.

That is a claim about the arithmetic only. It is not a claim that a dose is right for you, and no test can be written for that.

What this site cannot do

• Verify what is in your vial. Every calculation starts from the milligrams printed on the label. For an approved product that figure is verified; for a compounded or grey-market vial nobody has checked it, and no tool can.
• Tell you a dose to take. For drugs with an FDA label, the label’s schedule is reproduced and cited. For everything else no approved human dose exists, so there is nothing to report and nothing is invented.
• Know your concentration. That is set by the water volume you chose. It is the one input the site cannot infer, which is why every page keeps asking for it.
• Replace a clinician. See the medical disclaimer, which says this at greater length and means it.

Who writes it

One person: Kashif Khan, in Pakistan. Not a clinic, not a company, and not a vendor. That is worth stating plainly on a site about dosing, because it sets the limit of what it can be trusted for: the arithmetic is tested and the citations are checkable, and neither of those requires you to take anyone’s word for anything.

Every page carries that name in its byline, and the byline says what the name is not: a clinician. What it is, is the person who wrote the page, read the label or paper it cites, and checked that the figure on the page is the figure in the document. The work is editorial and arithmetical — finding the primary source, quoting it accurately, registering it so the citation cannot drift, and running the calculation engine’s test suite before anything ships. It is not clinical judgement, and no page here offers any.

That is also why the site prefers a verifiable sentence to a confident one. “The Saxenda label says review at 16 weeks” can be checked in a minute against the linked label. “Most people should…” cannot be checked against anything, so it does not appear.

There is no medical reviewer. No clinician has signed off on these pages, so none is claimed — no byline, no “medically reviewed by” badge, no invented credential. If you are a licensed clinician willing to review the dosing pages under your own name, get in touch.

How it is funded

Eventually, advertising — there is none on the site today. It sells nothing, stocks nothing and has no affiliate relationships with peptide vendors, which matters in a niche where most calculators are attached to a shop.

Corrections

If a figure here contradicts its source, or a source has been superseded, that is a bug and we want to fix it. Regulatory status in this area changes frequently — several of the compounds covered moved between FDA compounding categories during 2026 alone.

Send corrections to the contact address — naming the page, the figure and the document that contradicts it is enough. See the sources and methodology page for how decisions about what to publish get made, and the medical disclaimer for what this site is not.