Peptide
Calculator Hub
Eight precision calculators for research peptide reconstitution, dosage, concentration, purity correction, cost analysis, half-life decay, storage planning, and blend mixing. Built for scientists, updated for accuracy.
Peptide Reconstitution Calculator
Calculate concentration (mcg/mL) from vial size + bacteriostatic water volume
How to use: Enter your vial size (typically 2mg, 5mg, or 10mg) and the volume of bacteriostatic water you plan to add. The calculator shows the resulting concentration and automatically computes mcg per common draw volumes (0.1, 0.25, 0.5mL) on an insulin syringe.
Standard recommendation: 2mL per 5mg vial yields 2,500 mcg/mL — the most common research protocol concentration. Increase water for lower per-draw doses; decrease for higher concentration.
| Vial Size | BAC Water | Concentration | Per 10 units | Per 25 units |
|---|---|---|---|---|
| 2 mg | 1 mL | 2,000 mcg/mL | 200 mcg | 500 mcg |
| 5 mg | 1 mL | 5,000 mcg/mL | 500 mcg | 1,250 mcg |
| 5 mg | 2 mL | 2,500 mcg/mL | 250 mcg | 625 mcg |
| 10 mg | 2 mL | 5,000 mcg/mL | 500 mcg | 1,250 mcg |
| 10 mg | 4 mL | 2,500 mcg/mL | 250 mcg | 625 mcg |
What is peptide reconstitution concentration?
Reconstitution concentration is the ratio of peptide mass to solvent volume after dissolving a lyophilized (freeze-dried) peptide in bacteriostatic water. It is expressed in mcg/mL (micrograms per milliliter) and determines how many micrograms of peptide are in each unit drawn on an insulin syringe.
For research protocols requiring precise dose delivery, knowing the exact reconstitution concentration is essential. A 5mg vial dissolved in 2mL gives exactly 2,500 mcg/mL — meaning every 0.1mL (10 units on a U-100 syringe) delivers 250 mcg.
Dosage Per Draw Calculator
Find exact mcg delivered per insulin syringe draw
U-100 syringe: 100 units = 1mL, so 1 unit = 0.01mL. At 2,500 mcg/mL, 1 unit delivers 25 mcg; 10 units delivers 250 mcg; 25 units delivers 625 mcg.
Tip: If your target dose is 250 mcg and your concentration is 2,500 mcg/mL, draw to the 10-unit mark (0.1mL) on a U-100 insulin syringe.
| Syringe units | Volume (mL) | @ 2,500 mcg/mL | @ 5,000 mcg/mL | @ 1,000 mcg/mL |
|---|---|---|---|---|
| 5 units | 0.05 mL | 125 mcg | 250 mcg | 50 mcg |
| 10 units | 0.10 mL | 250 mcg | 500 mcg | 100 mcg |
| 20 units | 0.20 mL | 500 mcg | 1,000 mcg | 200 mcg |
| 25 units | 0.25 mL | 625 mcg | 1,250 mcg | 250 mcg |
| 50 units | 0.50 mL | 1,250 mcg | 2,500 mcg | 500 mcg |
| 100 units | 1.00 mL | 2,500 mcg | 5,000 mcg | 1,000 mcg |
Vial Cost Per Unit Calculator
Break down cost per mcg, per dose, and total doses from a vial purchase
Purity matters for cost: At 95% purity, a $39 vial delivers 4,750 mcg of active peptide — not 5,000 mcg. At ≥99%, you get 4,950 mcg. Higher purity = more active compound per dollar spent, which compounds across many doses.
HPLC Purity Correction Calculator
Find the true active peptide mass in any vial, corrected for purity
Why purity correction matters: Most peptides are weighed before the purity assay result is applied to the label. A 5mg vial at 97% purity contains only 4,850 mcg of the target peptide — 150 mcg of unknown synthesis byproducts make up the rest. For dose-sensitive assays, this 3% error compounds significantly.
| Stated Mass | Purity | Active mcg | Impurity mcg | True conc @ 2mL |
|---|---|---|---|---|
| 5 mg | 99% | 4,950 mcg | 50 mcg | 2,475 mcg/mL |
| 5 mg | 98% | 4,900 mcg | 100 mcg | 2,450 mcg/mL |
| 5 mg | 95% | 4,750 mcg | 250 mcg | 2,375 mcg/mL |
| 5 mg | 90% | 4,500 mcg | 500 mcg | 2,250 mcg/mL |
| 10 mg | 99% | 9,900 mcg | 100 mcg | 4,950 mcg/mL |
Peptide Half-Life Decay Calculator
Estimate concentration remaining at any time point using first-order kinetics
First-order decay assumes a constant fractional rate of elimination — the standard model for peptide clearance in preclinical pharmacokinetic studies. After 1 half-life, 50% remains. After 2 half-lives, 25% remains. After 10 half-lives, <0.1% remains.
Important note: Published half-life values for research peptides are estimates derived from preclinical studies and vary with route of administration, species, and individual biology. These values are provided for research planning only.
| Peptide | Approx. Half-Life | % Remaining at 1hr | % Remaining at 6hr |
|---|---|---|---|
| CJC-1295 (no DAC) | ~15–30 min | ~50% | <3% |
| CJC-1295 with DAC | ~6–10 days | ~99% | ~96% |
| GHRP-6 | ~20 min | ~15% | <1% |
| Ipamorelin | ~30 min | ~26% | <1% |
| BPC-157 | Variable, est. ~30 min | ~25% | <1% |
| TB-500 | Est. ~3 days | ~99% | ~94% |
| Fragment 176-191 | ~20 min | ~13% | <1% |
| Sermorelin | ~10–12 min | ~5–10% | <1% |
BAC Water Dilution Calculator
Find how much bacteriostatic water to add to hit your target concentration
Reverse reconstitution: Use this calculator when you know your target dose and want to set up your concentration so each draw lands on a convenient syringe mark. Enter your dose target and the calculator tells you exactly how much BAC water to add.
Freeze-Thaw Cycle Planner
Plan aliquots to eliminate peptide-damaging freeze-thaw cycles
Best practice: Aliquot immediately after reconstitution — before freezing the main stock. Each aliquot tube should contain only as much volume as you need for 1–2 sessions. This limits freeze-thaw cycles on each portion to <3, preserving peptide integrity throughout your protocol.
Label each aliquot with: peptide name, lot number, concentration, volume, preparation date, and cycle count.
How many freeze-thaw cycles can a peptide survive?
Most research peptides tolerate 2–3 freeze-thaw cycles without significant measurable degradation when handled correctly. Each freeze-thaw event causes mechanical stress through ice crystal formation and increased exposure to dissolved oxygen at the thawing interface.
- Peptides with disulfide bonds (Cys-Cys) — most vulnerable; limit to 1–2 cycles max
- Short, linear peptides (<10 residues) — more tolerant; often stable through 3–5 cycles
- Peptides with Met, Trp residues — susceptible to oxidative damage during thawing; minimize cycles
- Solution in BAC water vs plain water — BAC water’s benzyl alcohol does not protect against freeze-thaw degradation; the mechanism is physical, not antimicrobial
Multi-Peptide Blend Mixer
Calculate combined volumes and concentrations when drawing two peptides into one syringe
Peptide A
Draw order matters: When combining two peptides into one syringe, draw the smaller volume first. This minimises cross-contamination of the first vial if the needle tip briefly contacts the second peptide solution during the draw sequence.
Common research blends: CJC-1295 + Ipamorelin (synergistic GH release), BPC-157 + TB-500 (tissue repair stacking), Selank + Semax (cognitive research). Our pre-blended products provide both peptides in a single verified vial with one combined CoA.
Peptide Calculator FAQ
Answers to the most-searched questions about peptide reconstitution math, dosage units, and protocol planning.
1 mg = 1,000 mcg (micrograms). So a 5mg peptide vial contains 5,000 mcg of peptide (before purity correction). This conversion is essential for all reconstitution math: a 5mg vial dissolved in 2mL gives 5,000 mcg ÷ 2 mL = 2,500 mcg/mL. Most research peptide dosing protocols are expressed in mcg, while vials are sold in mg — always convert first.
It depends on your reconstitution concentration. On a U-100 insulin syringe, 1 unit = 0.01 mL. Therefore:
At 2,500 mcg/mL: 1 unit = 25 mcg. At 5,000 mcg/mL: 1 unit = 50 mcg. At 1,000 mcg/mL: 1 unit = 10 mcg.
Formula: mcg per unit = Concentration (mcg/mL) × 0.01. Use Calculator 02 above to compute this instantly for your specific concentration.
For 250 mcg per 0.1 mL draw (10 units on a U-100 syringe), you need a concentration of 2,500 mcg/mL. For a 5mg vial: 5,000 mcg ÷ 2,500 mcg/mL = 2.0 mL of bacteriostatic water. Add exactly 2.0 mL to the 5mg vial, and each 10-unit draw delivers precisely 250 mcg. Use Calculator 06 to solve the reverse — enter your target concentration and get the exact BAC water volume.
In the CJC-1295 / Ipamorelin research blend: CJC-1295 (Mod GRF 1-29) has an estimated half-life of 15–30 minutes in vivo, producing pulsatile GH release. Ipamorelin has an estimated half-life of ~30 minutes. Both clear rapidly, which is why the blend is typically used in research protocols timed to model acute GH pulse dynamics rather than sustained elevation. Use Calculator 05 above to model concentration decay over time for each component.
Formula: Cost per dose = Vial price ÷ (Vial mass in mcg ÷ Dose in mcg). Example: $39 vial / 5mg / 250 mcg dose = 5,000 mcg ÷ 250 mcg = 20 doses; $39 ÷ 20 = $1.95 per dose. However, always correct for purity first: at 99% purity, your 5mg vial contains 4,950 mcg of active peptide — not 5,000 mcg. Use Calculator 03 to handle purity correction automatically.
The 10mg vial typically offers lower cost per mcg — our 10mg vials average 15–20% less per mcg than two separate 5mg vials. However, the better choice depends on your protocol length. If you can use a 10mg vial within 4 weeks of reconstitution (refrigerator life), the 10mg vial is more economical. If your protocol uses <5mg over 4 weeks, stick with 5mg to minimize peptide wastage from degradation. Use Calculator 03 to compare cost per dose across vial sizes.
HPLC purity is the percentage of the sample that is the target peptide, measured by High-Performance Liquid Chromatography. At 99% purity, your 5mg vial contains 4,950 mcg of active peptide and 50 mcg of other compounds (synthesis byproducts). At 95% purity, you have 4,750 mcg active — a 200 mcg difference that compounds across many doses. For sensitive dose-response experiments, always use the purity-corrected mass in your calculations. Calculator 04 handles this correction automatically.