CJC-1295 and ipamorelin are compared constantly, usually as a pair — and the pairing is the point. They act on different receptors in the same growth-hormone pathway, which is why they are so often discussed together rather than as alternatives. But for the calculator, the interesting difference is not the receptors. It is the vial sizes and the amounts: CJC-1295 vials are small and its amounts are small, while ipamorelin’s most common vial is 5 mg and its amounts sit in the hundreds of micrograms. This page puts the two side by side so the arithmetic is clear before anything else.
What they are — briefly, and only what the maths needs
CJC-1295 is a synthetic analogue of GHRH (growth hormone-releasing hormone), the signal that tells the pituitary gland to release growth hormone. It is a 29-amino-acid peptide (molecular weight 3,367.9 g/mol). Ipamorelin is a synthetic pentapeptide — five amino acids, molecular weight 711.9 g/mol — that selectively activates the ghrelin receptor (GHSR-1a). Neither is FDA-approved for any indication, anywhere; both are sold as research compounds, and both are prohibited by WADA at all times under S2 (S2.2.4). Tesamorelin, not CJC-1295, is the only FDA-approved GHRH analogue.
CJC-1295 first: two forms, one name
This is the single most important thing to get right before calculating. CJC-1295 comes in two forms that share the name:
- With DAC (Drug Affinity Complex): the molecule binds serum albumin and lasts much longer — a half-life of roughly 6–8 days. Vials are typically 2 mg and 5 mg (10 mg vials are also sold).
- Without DAC: technically called Modified GRF (1-29) or Mod-GRF(1-29), with a half-life of roughly 30 minutes. Vials are typically 2 mg, 5 mg and 10 mg.
The two forms are pharmacologically different and must not be conflated — but the vial maths is identical for both, because concentration depends only on the milligrams on the label and the millilitres of water you add. Note the form on your vial before you calculate.
Ipamorelin: one form, one common vial
Ipamorelin has no DAC split to worry about. Vials are sold as 2 mg, 5 mg and 10 mg, with 5 mg the size most reconstitution guides use as their default example. It is the most receptor-selective of the growth-hormone-releasing peptides: unlike earlier compounds in the class, it does not meaningfully raise cortisol, prolactin or ACTH — a pharmacology fact that does not change the maths, but explains why the two are discussed together.
The amounts, side by side
Both peptides’ amounts are discussed in hundreds of micrograms, which makes this comparison cleaner than the BPC-157/TB-500 one — the scale is the same, so the differences come from the vial sizes:
Worked example — CJC-1295, 2 mg vial, 2 mL of BAC water, example amount 100 mcg:
- Concentration: (2 × 1,000) ÷ 2 = 1,000 mcg/mL
- Each unit holds 1,000 ÷ 100 = 10 mcg
- Units for the example amount: 100 ÷ 10 = 10 units (0.1 mL)
- Amounts in the vial: 2,000 ÷ 100 = 20 amounts
Worked example — Ipamorelin, 5 mg vial, 2 mL of BAC water, example amount 300 mcg (0.3 mg):
- Concentration: (5 × 1,000) ÷ 2 = 2,500 mcg/mL
- Each unit holds 2,500 ÷ 100 = 25 mcg
- Units for the example amount: 300 ÷ 25 = 12 units (0.12 mL)
- Amounts in the vial: 5,000 ÷ 300 = 16.7 amounts (about 16 full amounts)
Same amount, different vials
Take an example amount of 100 mcg and run it through both peptides’ most common vials with 2 mL of water: from a 2 mg CJC-1295 vial (1,000 mcg/mL) it is 10 units; from a 5 mg ipamorelin vial (2,500 mcg/mL) it is 4 units. Same amount, different answer — because the concentration is different. And if you use 1 mL of water instead of 2 mL in the CJC-1295 vial, the concentration doubles to 2,000 mcg/mL and the same 100 mcg becomes 5 units. The water volume is half the calculation, every time.
The blend vial
CJC-1295 and ipamorelin are also sold co-lyophilised in one vial, usually 5 mg + 5 mg — 10 mg total, never 10 mg of each. With 2 mL of water, each peptide is at 2,500 mcg/mL, so a draw of 4 units carries 100 mcg of CJC-1295 and 100 mcg of ipamorelin. Work out each peptide’s share separately; do not treat the total as one peptide’s amount.
Side by side
| CJC-1295 | Ipamorelin | |
|---|---|---|
| What it is | 29-amino-acid GHRH analogue | 5-amino-acid ghrelin-receptor agonist |
| Molecular weight | 3,367.9 g/mol | 711.9 g/mol |
| Forms | With DAC / without DAC (Mod GRF 1-29) | One form |
| Standard vial sizes | 2 mg, 5 mg (with DAC); 2 mg, 5 mg, 10 mg (no DAC) | 2 mg, 5 mg, 10 mg (5 mg most common) |
| Amounts discussed in | Hundreds of mcg | Hundreds of mcg |
| Example amount | 100 mcg | 300 mcg (0.3 mg) |
| Units at 2 mL water | 10 units (2 mg vial) | 12 units (5 mg vial) |
| FDA status | Not approved, research compound | Not approved, research compound |
| WADA | S2.2.4, prohibited at all times | S2.2.4, prohibited at all times |
What the comparison cannot tell you
Whether either peptide works, whether they work better together, which form of CJC-1295 to use, and whether any amount is safe or appropriate — none of that is a maths question. The human evidence for both is preliminary (comparison sources count roughly four human studies for CJC-1295 and five for ipamorelin, with no large trials). If you are choosing between them, that is a question for a licensed healthcare provider or pharmacist, not a calculator.
Frequently Asked Questions
Does CJC-1295 with DAC use different maths?
No. DAC changes the molecule’s behaviour, not the arithmetic. Concentration still depends only on the mg printed on the vial and the mL of water you add, and units are still volume × 100 on a U-100 syringe.
Why is my ipamorelin draw bigger than my CJC-1295 draw for the same amount?
It usually isn’t the amount — it is the concentration. A 5 mg ipamorelin vial in 2 mL is 2,500 mcg/mL; a 2 mg CJC-1295 vial in 2 mL is 1,000 mcg/mL. The same 100 mcg is 4 units from the first and 10 units from the second.
Can I calculate a blend vial as one peptide?
No. A 5 mg + 5 mg blend in 2 mL is 2,500 mcg/mL of each peptide separately. A draw of 4 units carries 100 mcg of each — work out each share on its own.
Which vial size should I use for the calculator?
The size printed on your own vial — and for CJC-1295, which form it is (DAC or no DAC). Do not assume a standard size.
Are CJC-1295 and ipamorelin interchangeable?
No. They act on different receptors (GHRH receptor vs ghrelin receptor) and are different molecules. That is a pharmacology question, not a maths one — and this site does not advise on it.
Which one should I choose?
This site does not answer that. Ask a licensed healthcare provider or pharmacist.
Try the calculator: Peptide Calculator
Related guides
- CJC-1295 Calculator
- Ipamorelin Calculator
- Reconstitution Guide
- How Much BAC Water Should You Add?
- mg to mcg Conversion Guide
Educational reference only — not medical advice. This guide describes maths and commonly reported handling steps only; it does not recommend any dose. Always confirm your dose and preparation with a licensed healthcare provider or pharmacist.