SteroidPlotter is the leading steroid cycle planner on the Web. Plot graphs and calculate levels for Anabolic Steroids, TRT & Peptides based on dosage & half-life.

Use our steroid plotter to plan and plot your cycle or protocol and share it with friends. You can start from scratch or get started by using one of our preset examples in the list below. You can include anabolic steroids, peptides, and pharmaceuticals.

Example Protocols

Click to view the protocol with graph.

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NOTE: We aim to make our calculator as useful as possible based on publicly available studies and data. However, there are significant limitations, assumptions are made, and a simplified pharmacokinetic model is used. The half-lives and pharmacokinetic variables used are estimates and will differ between individuals. This tool is for entertainment only and should not be used to make medical decisions. Always consult a healthcare professional before altering any medication regimen. This calculator and its content are not medical advice. Use at your own risk.


  • Where possible, we obtain the elimination half-life (t1/2), peak concentration (Cmax), time to peak (Tmax), and bioavailability (F(%)) of included compounds from peer-reviewed scientific studies.
  • Sometimes, certain pharmacokinetic values are less easy to ascertain. In these cases, we have to make assumptions to estimate these values, which will not accurately reflect the behavior of these compounds in real-world scenarios.
  • Pharmacokinetic data and studies/sources used for compounds used in the plotter application are included below.
  • Please visit our FAQs page for the most frequently asked questions we receive about the SteroidPlotter website & application.

Pharmacokinetics & Sources:

We are currently maintaining a Google Sheet listing current pharmacokinetics and sources. This sheet is a work in progress and will be ported to the website once completed.

If you have any feedback or suggestions or would like to see a new compound added, please do not hesitate to get in touch with us using our contact form or by joining our Telegram group.

54 thoughts on “”

  1. Mike here. Just wanted to ask did you get my answer to test enanthate/cypionate question? I used reply button. Also writed about other things.

    • Hi Mike. I’m on vacation for another week or so, so will a little while before I can reply to contact form messages and comments. Will get back to you later though.

  2. 250mg sustanon (iscaproate) twice a week yields serum levels almost double the same dose and schedule of test enanthate.
    How is this possible?

    • Isocaproate uses a simplified model due to lack of pharmacokinetic data available for that ester so it will be less accurate.

      That said, I’ve adjusted it’s multiplier so it will more closely match Test E (actually slightly lower blood levels due to the smaller half life).

    • What do you mean exactly? Tapering PCT meds down gradually? If you have an example we’d be happy to add it.

      • Tapering is a method in which steroid users reduce the dose by adjusting the endogenous hormone levels according to the steroid half-life without PCT, but in fact, I do not have an exact example.

    • Hey mate so I’m taking Test E 300mg 1ml per week for 10 weeks I just wanted to know are you saying it’s still not peaked yet ? This is my second cycle but this time I’m doing it properly as In sticking to the same amount for 10 straight weeks with a pct 2 weeks before finishing

  3. Did something recently get updated? I swear I am getting much lower concentration values on test enan than I was a few days go…

  4. is it valid to use 100mg masteron propionate with 150mg test enanthate 2x week? I’m using this now. I’m from Brazil so here we don’t have much access to the masteron enanthate wich would be the ideal. any suggestion ?

  5. In the dosage of testogel in mg, is the reference to total mg of gel or to the bioavailable ones? Since the bioavailability of the gel is around 10%. So a 50mg sachet would have a real 5mg.

  6. If propionate is taken daily, how long after the dose will it reach peak concentration? Would taking prop before bed at 10pm result in a peak concentration around 6-8am? I’m considering using prop for trt and attempting to replicate natural rhythm.

        • The pharmacokinetics of test prop we are using are as follows:

          half life = 1.0375 days
          Tmax = 1.0625 days

          The maximum plasma testosterone-19-d3 levels (15.0 ng/ml for subject 1 and 11.5 ng/ml for subject 2) occurred between 24 and 27 h.

          The full text of this paper has elimination half life listed as 26.7 hours in one subject and 23.1 for the other.

          Given the above, you’d expect relatively stable levels with a daily dose. If you’re looking for more variation between peak and trough consider EOD dosing.

          • Yes the half life has always been considered to be little more than 24h, so testosterone levels should vary, the old steroidplotter gave a totally different graph for propionate, the milligram release was actually cut in half from peak to through on a daily schedule.

          • The old site does not account for other pharmacokinetic variables so is considerably less realistic. It simply assumed instant release of all compounds which is almost never the case.
            Tmax is included in the new version which is the amount of time it takes for levels to reach Cmax (peak levels).

            Tmax is around 1 day, as is elimination half life. Half life starts after Tmax so you’ve got 2 days from dosing to hit peak then half. I realise this is not what people are familiar with seeing on the various plotter sites but it is far more accurate and based on actual scientific studies looking at blood levels after dosing.

          • I am confused. How can half-life (the time it takes to be at 50% of peak) be shorter the time to C-Max?

      • Great work!! This is something I have been missing for years. I have tried to calculate myself what blood concentration would be with a certain release rate. Mostly using my own laboratory results. A certain dose leading to certain blood concentration. So tried to calculate from there what amount of release would lead to what amount in blood.

        Testosterone enanthate and cypionate are way too different. Cypionate Tmax time is way too long. And Cmax should be equal to enanthate. Their pharmacokinetics are nearly identical. See Comparative pharmacokinetics of testosterone esters.

        • Thanks for the comment. The full text of the study you’ve provided doesn’t show an actual Tmax for cypionate. Do you know of any studies which include the actual pharmacokinetic data for cyp which more closely matches Test E, as seen in this study?

          • Unofortunately I do not know any studies that show numerical data of cypionate Tmax. But there is blood lab result data that show cypionate is very close to enanthate.

            For sidenote:
            Are you familiar that carrier oil can have big effect to half life? Example undecanoate in castoe oil half life 33,9 days, and in tea seed oil 20,9 days.

          • Quote from “comparative pharmacokinetics of testosterone esters”

            Because testosterone cypionate, testosterone cyclohexanecarboxylate and testos-
            terone enanthate had comparable suppressing effects on LH and consequently on
            endogenous testosterone secretion, it can be concluded from these studies in normal
            volunteers that all three esters with similar molecular structure possess comparable
            pharmacokinetics of exogenous testosterone serum concentrations. Testosterone
            cypionate or testosterone cyclohexanecarboxylate do not provide a more advanta-
            geous pharmacokinetic profile than testosterone enanthate. This observation is in
            agreement with a clinical study of replacement therapy with single-dose admin-
            istration of 200 mg of testosterone cypionate in 11 hypogonadal patients (Nankin

            For testosterone enanthate.
            Single-dose pharmacokinetics of testosterone enanthate after intramuscular admin-
            istration of 250 mg testosterone enanthate to seven hypogonadal patients and the
            best-fitted pharmacokinetic profile are shown in Fig. 14.6 (Nieschlag et al. 1976).
            Maximal testosterone levels in the supraphysiological range were seen shortly
            after injection (39.4 nmol/l, tmax = 10 h). Testosterone levels below the nor-
            mal range were observed following day 12 after injection. The calculated values
            were 9911 nmol ∗ h/l for AUC, 8.5 d for MRT and 4.5 d for terminal half-life
            (Table 14.2).

            And propionate:

            Single-dose pharmacokinetics of 50 mg testosterone propionate after intramuscular
            injection to seven hypogonadal patients and the best-fitted pharmacokinetic profile
            are shown in Fig. 14.4 (Nieschlag et al. 1976). Maximal testosterone levels in the
            supraphysiological range were seen shortly after injection (40.2 nmol/l, tmax =
            14 h). Testosterone levels below the normal range were observed following day 2
            (57 h) after injection. The calculated values for AUC were 1843 nmol ∗ h/l, for MRT
            1.5 d and 0.8 d for terminal half-life (Table 14.2).

            Difference between half-life and mean residence time;
            We want to use MRT. Actual time from peak blood concentration to half of it. Example peak concentration 40 nmol. 8 days later it is 20 nmol. Mean residence time 8 days.

            11.2.2 Mean residence time (MRT)
            In recent years more and more noncompartmental methods have been used
            for pharmacokinetic analysis. Twenty years ago statistical moment theory
            was introduced to pharmacokinetic analysis (Yamaoka et al. 1978). The times
            for the individual molecules to be eliminated can be described in terms of a
            statistical distribution function, i.e. the individual molecules can be elimi-
            nated just by chance within the first minutes or might still reside in the
            body weeks later. The mean residence time is a characteristic of this collec-
            tive behaviour and is the mean of the residence times of individual mole-
            cules (Cutler 1987). The mean residence time can be regarded as the statisti-
            cal moment analogy to half-life (t1/2) (Gibaldi and Perrier 1982).
            Assuming linear pharmacokinetics, the mean residence time (MRT) is
            characteristic for a special drug, independent of the administered dose. How-
            ever, mean residence time is a function of how a drug is administered. The MRT of a drug after non-instantaneous administration, e.g. intramuscular in-
            jection, will always be greater than the MRT after intravenous administration
            and can be regarded as approximately the sum of the MRT of the drug at the
            intramuscular depot and the MRT in the general circulation (Collier 1989;
            Mayer and Brazzell 1988; Yamaoka et al. 1978).

  7. why does trenbolone enanthate have such a long half-life? Is it by any chance trenbolone hexahydrobenzyl carbonate? and is it possible to add it in the future

  8. Could you please check the ester weighting and the half life of testosterone undecanoate? Speaking of Nebido (Bayer brand): Based on my blood work 88mg per week gives me blood serum levels of around 800 ng/dl. Based on your calculator it is in the low 500s:

    Professional information from Bayer indicates the half life is 53 days for instance:

    You might want to add different options for Undecenoate since pharmacodynamics differ depending on the carrier oil or the application method used (oral or injectable).

    • Hi. thanks for your comment.

      The study we used for most of the values of Test U used 750 mg TU in 3 mL of castor oil (, which I believe is the same formula as Nebido. They did not publish half life but from eyeballing the charts it looks to be about 20 days. We then found another trail which showed an average half life of 21 days (

      I’m not sure how best to handle adjustments to half life here as Bayer have published a half life different to what was seen in the trials but it looks like their Test U is basically the same as was used elsewhere. They just about provide enough in the document you provided to add as a unique compound (t1/2 = 52 days, cmax multiplier = 0.995049, tmax = 10.5 days), so we can go ahead and add it if that’s useful? The cmax and tmax are very close to the values we got from the other trials which is good.

  9. Thanks for the new planner.
    If you start Testosterone cypionate and have a slowly increasing concentration, how does the endogenous T you have/had naturally affect the concentration? Shouldn’t you be already saturated and start from a much higher level?

    • This is a great question and something we plan on improving on in the coming weeks.

      For now, the plotter does not account for endogenous testosterone and we have not yet accounted for it in our calculation of the Cmax multiplier. For example, if a study gave 100mg of Testosterone Cypionate which peaked at 1000ng/dl our Cmax multiplier would be 10ng/dl per 1mg Test Cypionate. If the study population were still producing endogenous testosterone, this obviously is not ideal and does not scale well across doses and also means our multiplier can vary based on the doses given in the trial.

      We are planning to improve this by accounting for endogenous levels in the study population, where available, or making predictions where not so. This should make levels in the plotter more accurate, assuming that users are fully shut down.

      And then there’s HCG which is another thing to consider in terms of its effect on endogenous T 😅

  10. I like the new layout, congratulations on the update.

    There seems to be a huge peak to trough difference for testosterone cypionate when compared with the old website?

    • Yes, there will be big differences/improvements for most compounds from the old version. Check our FAQs page for more info.

  11. I understand this is all based on scientific data, but some of it just doesn’t seem to pass the eye test. Incredible work here, no doubt, but I’m just slightly confused. For example:

    – In steady state, how does 10mg of Primobolan Enanthate (Injected ED) have a HIGHER peak than 40mg of Testosterone Suspension (Injected ED)?
    – 25 mg of Testosterone Propionate (ED) has a higher peak than 40mg of Testosterone Suspension (ED).

    I just don’t see how adding an ester to testosterone suspension actually makes it MORE potent / more ng/dL than without an ester.
    For example, using this plotter, if you inject 100mg of testosterone propionate ONCE, you peak out at 3,050 ng/dL. If you inject 100mg of testosterone suspension just once, you peak out at 1,520 ng/dL. Sure, the onset is quicker with suspension, but it should also have a higher peak, no?

    I know this is only based on science, and not your personal opinion, but it just seems odd to me.

    • So in your above example, primo is falling back to the less complex model as Cmax, Tmax, etc, were not available. Test Sus is using the more complex model, so out of the two, Test Sus will be the more realistic.

      That said, it has a half life of 10.5 days compared to Test Sus having a half life of 1.375 days. The compounds with a longer half life will absolutely reach a higher steady state, often at a much lower lower dose. This is simply what happens when considering the pharmacokinetics.

      A more extreme example:
      – Oral Primobolan: 0.2083 day half life
      – Testosterone Undecanoate: 21 day half life

      Now imagine taking 100mg of both compounds each day. By day 2, there is barely any primo in circulation, but almost all of the Test U is in circulation. We now add another 100mg dose, and the Test U almost doubles, whereas the oral primo is basically starting from zero. This compounds over time. In reality this is much more complex but if we think purely about half-lives then it can help understand why certain compounds build to much higher levels.

      Another example, there is often a misconception that NPP is lighter on side effects than Deca, but the reality is that it simply reaches a lower steady state on the same dose due to the pharmacokinetics:

      As for the different esters of Testosterone, they will definitely reach varying levels due to the Cmax and the Tmax. Different studies (which use different methods) are used to acquire the values we use, though, so the results from the plotter will not be highly accurate.

      • Actually, I think I may have pinpointed the issue for Testosterone Suspension. In the “Sources/Notes” section on the spreadsheet, you have the molecular weight of Testosterone Suspension listed as “412.6.” This number is the exact same molecular weight as Testosterone Cypionate, which is a heavy ester. If anything, Testosterone Suspension’s molecular weight should be nearly identical to 288.42.

        I think I see how this error occurred. Interestingly, if you Google “Testosterone Suspension molecular weight” the first result is “ts molecular formula is C27H40O3, and the molecular weight 412.61.” However, that textbox is actually pulling from an article discussing Testosterone Cypionate.

        Based on the data you have now, Testosterone Suspension (“412.6”) has a higher molecular weight than Testosterone Enanthate (“400.6”) which does not make sense.

        Beautiful work so far, just trying to help you work out the kinks! Cheers!

        • Well spotted! And really appreciate the feedback. This site will certainly rely on users like yourself letting us know what’s working as expected and what’s not otherwise it will be very difficult to get all the compounds dialed in. I’ve updated the doc. Will eventually have all the sources and figures output below the graph so it’s more obvious where we are getting data.

          Unfortunately, though, bioavailability is not utilised in the more complex model as we know the Cmax (the max blood levels based on a mg dose) so we can ignore bioavailability. I did double-check the source study and the reference values are from horses – don’t believe we could find any data on test sus in humans. We basically used a multiplier to try to get the levels to look more like they should in humans but looks like this was not a great match. I’ve adjust the multiplier so it more closely matches the prop levels after a single dose. Let me know if you think that looks more realistic or if further adjustment is needed.

  12. Really would like to see at least a toggle between ng/dl and mg released for the Y axis (or an option to view the old version.)

    • No problem. You can access it here:

      Just be careful using the old version as the release (mg/day) was a highly inaccurate way at looking at things and not reflective of what happens in reality.
      The new version uses Tmax and Cmax. Tmax being the time it takes for a dose to peak in the blood – this can be anything from a few minutes to many days. The old version of the site assumed everything was instantly released for every compound with is not realistic.

      • That is very interesting. I’ve been using that tool for over a year now as the main tool for planning my cycles (as well as stuff like front-loading during the first week.) Thank you for the continued evolution!


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