Advice On Transitioning From Test Cyp To Test Prop

Running 500mg/week of Cyp. Switching to 400mg/week of Prop. With the shorter ester, and therefore half-life, how long after my last pin of cyp (250mg 2x/week), should I start my 100mg eod of prop?

You can start as soon as you want, however if you’re looking to maintain very similar concentrations of testosterone because you’re paranoid about going higher (this is me, I meticulously plan out the dosing if I have to switch esters) you could taper up the test prop as the test E leaves you’re system, now I could figure out the maths for the exact doses but I don’t feel like it. A taper would be like this. So since you’re switching to 400mg test prop, say seven days after the last test pin (test E has a HL of roughly 7 days), however this will differentiate between individuals based on metabolism and elimination rates of testosterone. So one week after start test prop at 30mg/day, the next week go to 45mg/day then the next week full dose, you get what I’m saying. Don’t use those exact doses specified because im no expert, I was just stating a strategy you could implement to keep you’re testosterone levels relatively stable during the switch.

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Really could use some better advice for transitioning. If half of the cyp that is in my system is gone in 6 days (~500mg/week so ~250mg gone), shouldn’t I start my eod of prop 100mg ~3.5 days (time I would normally pin the next 250mg of cyp) after my last cyp pin? System would have used about 125mg and have about 375mg in system still. Sounds about a good time to start building my 400mg/week of prop. Totally crude and very rudimentary math here, just shows; help!!

Ok I myself usually switch from enanthate to prop on my last three weeks of long estered cycles.

I have always just pinned the enanthate on Sunday and Wednesday. If my last enanthate was Wednesday I start the prop on Sunday. HOWEVER I have recently discovered the steroid calculator and you find it by searching steroid calc. It graphs the amount of (in this case testosterone) a compound in the blood for that day.

I plugged in your dosage. You went from between 40 to 60 mgs a day on the cyp to between 25 to 80 mgs per day on the prop. And the first week on the prop you spiked up to almost 105 mgs per day a couple of days. Here is a screenshot.

For your calculations I did 12 weeks on the cyp then 8 weeks on the prop just to see how much of a time the cyp stayed in at a level to elevate the prop shots.

I do not know if the mgs per day are the total weight with ester or if it is elaborate enough to calculate just the free hormone weight.

Go to the site and play with it if you really want to keep it as even of a transition as possible. They also have the app for your phone, steroidcalc.

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Not really, you see over time the test cyp build up in Ur system. So you have much more than 500mg in you’re system at the time of ceasing use, I forget the exact equation and since I’m studying for exams I don’t have the time, will help afterwards if you still need it. Best of luck tho (I just use the site, I’d be too paranoid too download an app that has the word steroid on it lol)

Problem with the steroidcalc app is that they use their half lives based off a study with monkeys. The half life of test E is more like 7 days, not 4.5, granted it’s not much of a difference so it’s still a really cool app, also the concentrations will differ from person to person so take it as a guesstimate

Add those day plots up(every other dot), it’s right about 125, half of the 250 mgs of enanthate pinned on the start of the week 1. By day 10 it is a little over 125 but ultimately this is just a rough tool to use as a guide. I would have to go plot every ester but I bet they used the commonly listed half lives for all of them.

And this answers my question, this does not calculate the hormone free of the ester.

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I wonder how much money the guy who made the steroidcalc website made haha, probably gets like 1 cent per visit, probably gets like ten thousand visits + per day. Over time that’s a nice side income he can use to… Buy steroids.

I didn’t see any adds on it. The site and the app look the same. It’s just, and I assume he used JavaScript, HTML code with a JavaScript like input. Someone smarter than me could probably go look at the code and just copy the calculator part of it. My HTML class was over a decade ago but that site looked like I could have made something similar. I am NOT knocking it, it was done by one of “us” and he shared it. So I am grateful.

Now that I say all that I would bet it was a college Meatheads project where he had to make a input driven interactive site with a visual data output and or app that included so many possible calculations. I know I had to make a site/page in my HTML class, I did a store front with like 5-6 things you could buy. Shipping was free I didn’t want to deal with multiple inputs from one item. It was my sister’s art work so the site was very colorful and I had a hell of a time getting the text to show up well against the background, I didn’t want to have to deal with text boxes and selecting the size or color of multiple things per page. Things were simpler back then.

Oh, this is amazing, thank you!

He does have a donate Bitcoin option. Wonder if it’s ever worked

I played with it a little and I think I’ll just do as you mentioned. I planned to start my prop (100mg eod) on the day that I would normally pin my next cyp. I may have increased levels for a few days but at the same time I’m not sure I have a full ML of cyp for my next pin anyway so maybe that’ll balance things a little. (Fingers crossed) Ha!