Aromatase Inhibitor and Estrogen Blocker deference?

Good day

i need some help in understanding the difference between a Aromatase Inhibitor and an Estrogen blocker

I know both are anti-Estrogen drugs

i have read through multiple websites,William Lewellyns Anabolic cookcbook and literally 50-100 videos and research
no where can i find a easy explanation on what the difference between the two are
i know the name almost say it all, but if i search a product such as Arimadex i find sites that say its an aromatase inhibator and on other sites they say its and estrogen blocker
They also suggest to use Aromatase Inhibitor during cycle and estrogen blocker for past cycle - but once again vice versa

getting back to the question 
what is the difference between the 2
also which is better for during cycle and which is for post cycle

appreciate in advance

You get different types of anti-estrogens/estrogen blockers. The two common types in bodybuilding are Aromatase Inhibitors (AI's) and Selective Estrogen Receptor Modulators (SERM's).

Anastrozole, Letrozole and Exemestane are Aromatase Inhibitors.

Clomiphene and Tamoxifen are SERMs.

The question is, what is your Testosterone dosing that you are worried about estrogen, if you getting estrogen based sides it's easier, to cut back on the test to no more than 3mg per kg, and up your anabolics like dhts and 19nors

An aromatase inhibitor blocks the enzyme aromatase from converting testosterone to estrogen.

Other estrogen blockers like Nolvadex and Clomid (SERMS) bind to your estrogen recepters, basically blocking them off so that circulating estrogen can not bind to the receptors and activate estrogenic responses like the side effects we are trying to avoid.

With AI's you could lower your estrogen levels to close to zero, whereas with SERMs you can have high estrogen levels but very few available receptors for it to bind to. 

Thanks for interest in my question
Im just doing general research and information on what the difference is since there is many sites and books and videos which doesn't give a proper answer

Great answer and appreciate

What will you suggest is best for during cycle(if high estrogen levels accure for example as they say itchy or puffy nippels)

As well as post cycle


I dont have any side effects of estrogen but just incase it will happen

Once again appreciate the time and answer

if estrogen is too high that means your test levels are too high, lower testosterone and down comes estrogen usually happens at above 3mg per kg.

Thanks once again

If dont mind pleas help me understand

So once you use a synthetic testosterone like in a cycle to gain muscle mass (with proper diet and training) and it start raising estrogen and might cause to much

Therefore you lower testosterone do bring down the estrogen?

But once you lower the testosterone to bring down estrogen wont this defy the purpose of using test in a cycle to gain size

(I can understand in a medical situation where the aim is not to gain mass and blood testing will work best to know your level)

No, you are using Testosterone to a certain level to enhance hormones. Any more than a certain threshold brings side effects. That is when you add other compounds in. Start a cycle at 5mg per kg of which 3mg comes from Testosterone. Titration up of other compounds to fill the 2mg-7mg per kg. Simple as that.

Let's say you are 80kgs. So max dose is say 10mg per kg so 800mg per week.

You start at 400mg per week( 250 from test 150 from say 75mg of npp and 75mg of masteron) by week 8 you want to be at the full 800mg. So every 2 weeks you bump up by 100mg per week. Then you cruise out the rest of the 8 weeks at max dosing.

Appreciate your effort thank you for the time🙏

If i have more questions in will ask you💪

But once you lower the testosterone to bring down estrogen wont this defy the purpose of using test in a cycle to gain size

(I can understand in a medical situation where the aim is not to gain mass and blood testing will work best to know your level)

aas is a drug , so the dose is dependent on the users bodyweight plus experience. Think how little alcohol a small person needs to consume to get drunk vs a bigger person. same result but from a different dose. add years of continuous usage and the dose goes up as tolerance builds up ( I'm just using this to simplify it as much as possible , aas and alcohol are miles apart )