Which bathroom radiator, how many watts?

I want to renovate my bathroom, but now I am totally unsure which bathroom radiator I should buy. My bathroom is about 10 m², exterior walls insulated, new window. Heating system condensing gas. How many watts do I need at least. When googling on the internet, it gets really confusing...Thank you

How many watts do I have to take at least.

The power requirement depends on the room heating load. The capacities of the radiators are specified by the manufacturer for defined conditions (supply temperature, return temperature, room temperature) standard conditions e.g. DIN EN 442. If these differ, a correction is necessary. The required mass flow must correspond to the power needed.

v.g.

Since I was in the same (emergency) situation as steelers77 until recently, here is my two cents:
There is a simple rule of thumb to calculate the required heating load for a room. It is:

Bathroom size x heating capacity = heating load (i.e., how many watts you need).

Heating capacity for new buildings: 100 watts per sqm
Heating capacity for old buildings (uninsulated): 150 watts per sqm

So if it is a new building and a 10 sqm bathroom, it looks as follows:
10 sqm x 100 watts/sqm = 1000 watts

Your bathroom radiator should therefore have at least 1000 watts.