Quick answer

The Live Testosterone Readout on My Protocol is an estimate of your Total T right now. It climbs after each dose you log, drifts down toward trough before the next one, and is calibrated to your own blood test and the protocol that produced it, not a population average.

What it lets you see

A blood test gives you one point on a curve that moves every hour of the week. The readout fills in the rest of that curve, which answers questions a single draw can't:

How high your level climbs after a dose, and how far it drifts before the next one.
Where you are when you feel your best. If energy, mood, or libido dip on certain days, you can check whether those days line up with the low point between doses.
What a frequency change does. Split the same weekly dose into more frequent injections and the range tightens. Spread it out and the range widens.
When your level actually peaks after an injection or application.

Answering any of these with bloodwork would take a series of draws at different points in your dosing schedule. The readout estimates them from one blood test, your Protocol Log and published pharmacokinetics.

Why it starts from your blood test

Men on the same dose can end up at very different levels, because some respond more strongly to a dose than others. Your Responder Type describes where you sit.

TRT Plus does not use a population average to estimate your level. That would be like My Fitness Pal giving you a population average weight, landing you at 200 lbs and 30% body fat no matter what you ate.

Your readout starts from your own blood test. It knows where in your dosing schedule that blood was drawn and which protocol produced it, then runs forward on the doses you log.

How it works

The anchor. Your Total T result is one point on a curve that rises and falls between doses. It is first converted to the average level of the protocol that produced it, so a peak draw and a trough draw lead to the same place (Behre & Nieschlag, 1998; Pastuszak et al., 2022). If your log shows a testosterone dose change shortly before the blood test, the baseline allows for levels that hadn't settled yet.

Delivered testosterone, not label milligrams. An ester adds weight the body has to cleave off, so 100 mg of cypionate carries about 70 mg of testosterone and enanthate about 72 mg. For creams, the model uses what your application site actually absorbs, which levels off at higher doses (Bhasin et al., 2018).

Every dose adds up. Your level today is the sum of every dose in your Protocol Log, each with its own fading tail. An earlier ester in your log keeps its own half-life, so a compound switch is handled dose by dose.

It rises rather than jumps. A dose is absorbed over time rather than landing in the bloodstream at once, so each one climbs to a peak and then falls (Garrett, 1994). The absorption rate is set so the readout peaks where the Levels chart draws its peak.

Where you are now. Each dose from your Protocol Log is placed at the time it was logged. Marking today's dose as taken switches the readout from falling toward trough to climbing toward peak.

Live Testosterone Readout

Live Testosterone Model

\begin{gathered} \text{Live Testosterone Readout:} \\[0.4em] T(t) = \underbrace{\frac{7\,T_{\mathrm{draw}}}{\mathcal{E}(D_0)}\,\frac{\langle C_{ss}\rangle_W}{C_{ss}(t_{\mathrm{draw}})}}_{\text{your baseline}} \sum_{i\,:\,t_i\le t}\underbrace{\mathcal{E}_i}_{\text{logged dose}} \\[0.4em] \times\,\underbrace{\frac{k_{e,i}\,k_{a,i}}{k_{a,i}-k_{e,i}} \left(e^{-k_{e,i}(t-t_i)}-e^{-k_{a,i}(t-t_i)}\right)}_{\text{absorption + elimination}} \\[1.4em] \text{Dose Times:} \\[0.3em] t_i \in \underbrace{\{\text{Protocol Log}\}\cup\{t_{\mathrm{tick}}\}}_{\text{today counts once taken}} \\[1.4em] \text{Steady-State Superposition (your baseline):} \\[0.3em] C_{ss}(t) = \sum_{j=1}^{n} R_j(t-t_j), \quad \langle C_{ss}\rangle_W = \frac{1}{|W|}\int_W C_{ss}(t)\,dt \\[1.4em] \text{Delivered Testosterone (per route):} \\[0.3em] \mathcal{E}(D) = \begin{cases} D\,\varepsilon & \text{injectable}\\[4pt] \dfrac{V_{max}\,D}{K_m+D} & \text{transdermal (saturating)} \end{cases} \qquad \mathcal{E}_i = \frac{\mathcal{E}(f_i\,d_i)}{f_i} \\[1.4em] \text{Absorption \& Elimination:} \\[0.3em] k_{a,i}: \; \left(\operatorname*{arg\,max}_{t\,\in\,W}\,\sum_j A_i(t-t_j)\right) - t_{j^{*}} = \Delta t_{\mathrm{peak}} \\[0.4em] k_{e,i} = \frac{\ln 2}{t_{1/2,i}}, \quad t_{\mathrm{draw}} \in \Big\{\text{trough},\;\text{peak},\;\underbrace{t_{\mathrm{app}}+2.5\,\mathrm{h}}_{\text{cream peak}}\Big\} \\[1.2em] {\scriptstyle \text{Parameters:}} \\[0.2em] {\scriptstyle d_i = \text{logged dose}, \quad f_i = \text{doses per week}, \quad D_0 = \text{weekly dose at your blood test}} \\[0.3em] {\scriptstyle \varepsilon = \text{ester fraction}, \quad t_i = \text{logged dose times}, \quad W = \text{steady-state window}} \\[0.3em] {\scriptstyle A_i = \text{single-dose response}, \quad t_{j^{*}} = \text{dose before the peak}, \quad t_{1/2} = \text{half-life}} \\[0.3em] {\scriptstyle R_j = \text{route-specific release}, \quad V_{max},\,K_m = \text{site saturation}, \quad t_{\mathrm{app}} = \text{cream application time}} \end{gathered}

After a protocol change

The readout follows the doses in your Protocol Log. Change your compound, dose, or frequency and it climbs or eases toward the new level as you take each dose, the same way your blood does. The Live T explainer also shows where your current protocol settles and roughly by what date.

How long that climb takes depends mainly on the compound, at about five half-lives:

Compound	Half-life	Time to settle
Cream / topical	0.5 days	3 days
Propionate	1 day	5 days
Enanthate	4.5 days	23 days (3.2 weeks)
Cyp/Ent blend	6.25 days	31 days (4.5 weeks)
Sustanon	7 days	35 days (5 weeks)
Cypionate	8 days	40 days (5.7 weeks)
Decanoate	10 days	50 days (7.1 weeks)
Undecanoate (Nebido)	48 days	240 days (34.3 weeks)

What it assumes

The anchor is one blood test, so the readout is only as current as that test.
Response is taken to scale with dose. That holds across the TRT range and is weaker at supraphysiological doses.
Half-lives are published averages from clinical studies, so the shape of your levels between doses is typical rather than measured. How high your level sits comes from your own blood test.
Before your log starts, the readout assumes you were on the first protocol you logged. From then on, a day with no dose logged counts as no dose. Today's dose is timed from when you mark it as taken.
It models blood testosterone. It does not measure it.

Switching it on

Without a baseline, the readout shows a dash. The pulsing dot on the Testosterone Fluctuation chart still shows where you are between doses, but turning that into a level needs a blood test paired with the protocol that produced it.

That pairing happens when you generate a bloodwork report. The report pairs your result with what you were taking in the weeks leading up to the draw, from your Protocol Log or by asking you, and the readout switches on.

The Live Testosterone Readout is an educational estimate, not medical advice, and it does not replace bloodwork. Consult with your healthcare provider before making medical decisions.

Your Testosterone Level, Right Now