How long roughly can the process of transitioning take and how do I know I 100% want this?

Depending on what you want, it can take weeks, months, or years.

Let's start with easier, quicker, and more reversible steps. This means going by a different name or pronouns, wearing different clothes, cutting your hair, possibly coming out to the people you know.

Next is the less irreversible steps, and the one you've heard of many times: hormone therapy. Going on hormones have some irreversible effects (voice change, body hair, bottom growth) and some reversible (fat redistribution) effects. Take note that the effects have hormones take years to develop, much like cis people going through puberty. It can take years for you to grow a beard, much like how a cis man can't grow a beard until he's in his 30s. Sometimes it doesn't take that long. Everyone's different. This also applies to hair loss as well.

And arguably the most irreversible: surgery. Many people get top/bottom surgery after they take hormones. Also, you're given an anesthetic during surgery to knock you out so you don't feel any pain while they do the work! Surgery is also a multi-step process that can take up to months or years, depending on what you're getting and possible complications. Surgery isn't done in an instant; there are revisions, check ups, etc.

And this all leads me to my final point: transitioning is a lifelong process. Not only does it involve what I mentioned before, but it involves changing your IDs, social security, possibly birth certificates... Many legal issues also come up with this. This isn't meant to scare you or anything, but transitioning isn't a "stop and done" thing. Transitioning isn't going from hormones to surgery, and then you're done. Every day feels like a little bit of progress, and gradually you feel like yourself. There's no "set" moment when you're finished and there's nothing left to do.

This is just my two cents.

 

meltyblood had some good things to say.

The process takes a long time and there are quite of few checks on the way to reduce the chance of regret. Regret is much rarer than many make it out to be and there are a lot of people who are hurt more by all the gate-keeping. Also, there are people who have gone all the way thru getting top and bottom surgery and then detransitioned (rare but it can be done though going back to exactly where you were prior cannot happen). I detransitioned twice due to pressure from significant others, family and society (I SERIOUSLY regret submitting to those horrible people in my life now and wish that I had just cut them out and moved on with living as my true self).

It depends on a lot of factors. Where you are and what access you have to care (this even varies within a single country). How much money you have (if you can spend all that you want you can go very quickly within private healthcare). Exactly what you want: some only socially transition with no medical so only paperwork. Some only take hormones and socially transition. Some only have one or two surgeries while others get quite a few. I think the fastest that I have heard of is about a year for someone with a LOT of money. I on the other hand started in 1986 and have not yet had vaginoplasty though I have lived full time as a woman since 2006 (legal ID change in 2007).
Last I heard in the UK it takes about a year to get the process started and during that there are no permanent changes. After starting hormones you can stop them and many effects revert like body fat distribution. Once your voice deepens though that is permanent without surgery on your vocal cords (last I heard there were two surgeons in South Korea who would do that). Facial hair that develops is also permanent without laser/electrolysis. If you take full hormones for an extended period of time then some surgery is necessary (minimum of orchiectomy for M2F and radical hysterectomy for F2M)

This depends on which surgery and each person, I have had a number of surgeries (most not transition related) and some were only annoying while others were really bad. Everyone feels pain differently. As mentioned above while the surgery actually happens you feel nothing. The recovery time and pain depends on the surgery. Top surgery is less invasive and the trans guys who I have known who did it were more uncomfortable than in serious pain during healing. Bottom surgery is more invasive and takes longer but everyone who I have know who had it stated that it was easily worth it.

 

Changes from hormones start to be visible after a few months and it depends on the person how long it will take you to pass, but typically all changes happen in about 2 years. Most people manage to change their ID etc. and get top surgery during this time, as hormoes are doing their job.

As for not regrertting it, I have no clue. I feel like you always take a risk of regretting serious decisions like that. A ton of things can go wrong, after all. Psychologists doing trans diagnoses ask questions about things that would typically lead to regret, like how you actually feel about your body and if you don't feel distressed about it, you might regret changing it, or if you feel nonbinary or are too unlike the gender you want to transition to, however, it isn't set in stone that it works this way, so these questions are more for self-reflection. One thing I would look out for is unrealistic expectations, they seem to be a common point for regret and problems many people who transition face. For example, relying on transition to fix your bad mood and it might turn out it helped a bit, but it was not all there was to it. Or having unrealistic expectations what it means to be perceived as a man or a woman or expecting that you wouldn't have to take hormones for the rest of your life or not being fully aware of the infertility.

 

I don't mean that you have to have unrealistic expectations. I said this because you asked how to be sure if this is the right choice. Sorry if I misread it. But yes, unrealistic expectation are pretty common.

 

Yup. Side effects ... wrt body hair - obviosly, looking otherwise like a man And wrt looking like a man... infertility, possible ovarian and uterus cancer plus all the usual stuff associated with taking medications, probably, like liver problems.

 

I mean, I say cancer, but it's more like malfunction of the ovaries and the uterus, I suppose. If ovaries malfunction, they can become lumps of cysts, and if you don't menstruate, the uterus lining can become pafhological. It doesn't depend on family history or cancer. And it's the reason why it's advised to anyone going on HRT to get surgery to remove these organs. So... that's pretty serious. And unfortunately, it's frequent among persons on HRT.

 

Just so people know, it works in a similar way for those assigned male at birth who get HRT, the testes should be removed (which is a lot less invasive and easier to do). I had to wait almost 30 years because insurance refused to pay until I was diagnosed with a precancerous condition.

 

Well, in terms of mental health, I would say transition is just one aspect of it. A fraction. If you need it and transition, it gets better, but there are also things like the need to be independent financially, childhood attatchment issues / healthy relationships, self-regulation, how you feel about really anything in your life...

 

And in terms of happiness, generally, too.