Creatine Lab

A solubility and body-pool estimator. Not medical advice, not a dose, and not a lab interpretation. It uses published solubility, stability and loading data with a simplified body-pool model. It cannot tell you whether creatine is safe for you, what to take, or what your creatinine or eGFR result means. Ask a clinician. Use at your own risk. Open for the full scope limits.

Model scope

This calculator uses published solubility, stability and loading data with a simplified body-pool model. Solubility figures use temperature-only water data, and body-pool results are rough population estimates.

Do not use it to

Diagnose kidney function.
Interpret creatinine or eGFR labs.
Choose a dose.
Decide whether creatine is safe for you.
Replace clinical care.

Creatine supplementation can raise serum creatinine without any kidney injury, because creatinine is its breakdown product. A result read without that context can look like reduced kidney function when it is not, and only a clinician who knows you are supplementing can tell the difference. This tool cannot.

Ask a clinician before using creatine if

You have kidney disease or abnormal labs.
You are pregnant.
You take medicines that affect the kidneys or fluid balance.
You have symptoms or medical conditions that could change supplement risk.

What the numbers are not

Solubility here is for creatine in water at a temperature. A real drink has other solutes, a different pH and a different history, and it does not behave the same way.
Body-pool figures are population estimates. Individual response varies widely, and muscle creatine content, diet and body composition all move the answer.
Stability data describe storage conditions in the cited studies, not your bottle in your kitchen.
Nothing here is a measurement of you. These are not personal lab values and cannot be substituted for one.
Supplement products vary in purity and in what else is in them, and nothing on this page speaks to a specific product.

Verify independently

Check the cited sources and use qualified medical, nutrition, laboratory or regulatory guidance before using any result for health, safety, clinical, commercial or other consequence-bearing decisions.

No warranty. No liability. No suitability claim. You assume all risk. The tool is provided as-is and as-available, without warranty of accuracy, completeness, merchantability, fitness for a particular purpose, medical suitability, regulatory acceptability, or lab-interpretation value. To the maximum extent permitted by law, the author accepts no liability for any loss, injury, illness, death, damage, cost or claim arising from use of or reliance on this page, and the author and maintainers expressly disclaim responsibility for dosing decisions, supplement decisions, lab-test interpretation, medical decisions, adverse events, commercial losses, downstream damages, or any other consequence arising from use or misuse of this page.

No professional relationship. Using this page does not create any medical, clinical, nutritional or professional relationship, and nothing on it is medical, clinical, nutritional or professional advice. It is not a substitute for consultation with a qualified clinician who knows your history.

Independent verification required. Check every figure against the cited sources and a qualified clinician before acting on it. Those sources and professional medical judgement control; where this page disagrees with them, this page is wrong.

Consequential damages excluded. To the maximum extent permitted by law, in no event will the author or maintainers be liable for any direct, indirect, incidental, special, exemplary, punitive or consequential damages, including injury, illness, adverse events, misread laboratory results, commercial losses, or loss of use, data, profits or business interruption, however caused and on any theory of liability, whether in contract, strict liability or tort including negligence, arising out of or in connection with this page, even if advised of the possibility of such damage.

Indemnity. By using this page you agree to indemnify and hold harmless the author and maintainers against any claim, demand, loss or expense arising out of your use of it or of anything derived from it.

Severability. If any part of this notice is held unenforceable, the remainder continues to apply, and the unenforceable part is limited to the least extent necessary rather than struck out.

Inputs

Creatine monohydrate only. Dose inputs are grams of creatine monohydrate, not other forms.

Settings auto-save to this browser as you type.

Ready.

Mix

Creatine monohydrate

Water volume

Water temperature

Drink the full bottle or suspension

Advanced model parameters

FFM to SMM fraction Muscle creatine g/kg

Muscle share of pool Endogenous synthesis

Turnover per day (%) Baseline saturation (%) Muscle uptake Vmax

Muscle uptake Km

Pool gap Hill exponent Temperature Q10 Monte Carlo draws Brain reference low (%) Brain reference typical (%) Brain reference high (%)

Results

Solubility uses temperature-only water data. Body-pool results are rough estimates, not personal lab measurements.

Estimates, not measurements of you. Solubility uses temperature-only water data and body-pool figures are population estimates, so neither describes your drink or your body. Nothing here is a dose, a lab interpretation or medical advice. Creatine can raise serum creatinine without kidney injury; tell your clinician you are supplementing.

Dissolved at equilibrium 0.00 g Waiting for input.

Suspended powder 0.00 g Waiting for input.

Solubility limit 0.00 g/L Waiting for input.

Water needed 0 mL Waiting for input.

After storage 0.00 g Waiting for input.

Dissolved loss 0.0% Waiting for input.

Estimated creatinine formed 0.00 g Waiting for input.

Final body pool 0 g Waiting for input.

Pool basis 0 g Waiting for input.

Modeled saturation 0.0% Waiting for input.

Waste pressure 0.00 g/day Waiting for input.

Estimated SMM 0.0 kg Waiting for input.

Brain tCr estimate 0.00 g Waiting for input.

Brain tCr ref gain 0.00 g Waiting for input.

Monte Carlo band 0.0% to 0.0% Waiting for input.

Additional steady dose 0.00 g/day Waiting for input.

Creatinine output 0.00 g/day Waiting for input.

Retention efficiency 0.0% Waiting for input.

Diet-supported equilibrium 0 g Waiting for input.

Mass-balance residual 0.00 g Waiting for input.

Dissolved Loss Over Storage

Waiting for input.

Estimated Saturation And Dose Pressure

Waiting for input.

Daily Creatinine Production

Waiting for input.

Fate Of Supplemental Dose

Waiting for input.

Cumulative Dose Vs Retained

Waiting for input.

Days To Estimated Saturation

Target	Centerline	10-90% band	Reached in draws

How To Use This Tool

Step	What To Do
Start with the question	Use this tool for three separate questions: whether a dose dissolves in a selected water volume and temperature, how the degradation rate affects dissolved creatine during premixed storage, and how a selected protocol changes a rough body-pool estimate. The tool models creatine monohydrate only. Dose fields are grams of creatine monohydrate powder, not grams of active creatine and not other creatine forms.
Pick a preset	Start with Default bottle, Fridge bottle, Small glass, or Warm dissolve. Then change only the inputs that actually differ from your scenario. Default bottle is useful for 5 g in 1 L at room temperature. Small glass shows why grit can remain in a low-volume drink. Fridge bottle means water is stored first and creatine is added later.
Use Mix	Set creatine monohydrate, water volume, and water temperature. Read Dissolved at equilibrium, Suspended powder, Solubility limit, and Water needed. Dissolved and Suspended describe the bottle or glass. Suspended powder is not automatically wasted if the full suspension is consumed promptly.
Use Store	Use Store to describe whether storage happens after mixing, before creatine is added, or as dry powder. Only the premixed solution/suspension mode runs the aqueous degradation-rate calculation. The model first estimates the dissolved amount at storage temperature, then applies first-order loss to that dissolved amount. Water stored by itself and dry powder do not use the aqueous degradation model.
Use Accumulate	Pick a protocol and simulation length. Use direct skeletal muscle mass if you know it; direct fat-free mass is next best; body mass plus body fat is only a proxy. Modeled saturation, steady-state dose, waste pressure, and Monte Carlo band are model outputs. They are not dosing instructions or personal measurements.
Read the caveats	The brain tCr estimate is a separate reference estimate and does not change with the selected protocol. Body-pool values are rough estimates driven by assumptions. This tool does not decide whether creatine is safe for you, recommend a dose, diagnose kidney function, interpret creatinine/eGFR labs, or replace clinical care.

Cross-Study Harmonization

This tool is composed from heterogeneous human studies. Cooper 2012 supplies the baseline body pool, NCBI Bookshelf supplies the 1.7%/day turnover constant, Hultman 1996 anchors the loading curve and the slow-load endpoint, Harris 1992 and Greenhaff 1994 supply the responder spread, Burke 2003 and Lukaszuk 2002 supply the vegetarian baseline shift, and Walker 1979 supplies the creatine-to-creatinine mass ratio. None of these anchors were measured on the same individual or on the same cohort, and few of them sampled women, older adults, or untrained populations adequately.

The Monte Carlo envelope is how the model absorbs that heterogeneity. It samples the inputs we know vary across people: baseline pool size, muscle creatine concentration, turnover fraction, transporter Vmax and Km, dietary intake, and baseline saturation. It then surfaces a 10-90% band so you can see how those known unknowns propagate to the predicted curve. It is not a statistical confidence interval, it does not capture sex differences, age effects, fiber-type composition, training status, or insulin co-ingestion, and a real person's trajectory can comfortably sit outside it.

Read the band as: this is roughly where the model expects most people who match the entered inputs to land, after accounting for the input ranges we sampled. Treat tighter point estimates with appropriate skepticism; every "centerline" in this tool is built from averages of averages.

Model Notes

Model Sanity Checks

Status	Check	Fixture / anchor / model check

Claim Audit Trail

Area	Claim / implementation	Support / source

Model scope

Do not use it to

Ask a clinician before using creatine if

What the numbers are not

Verify independently

Inputs

Mix

Storage

Accumulation

Brain Compartment

Results

Dissolved Loss Over Storage

Estimated Saturation And Dose Pressure

Daily Creatinine Production

Fate Of Supplemental Dose

Cumulative Dose Vs Retained

Days To Estimated Saturation

Estimated Saturation And Dose Pressure