I checked and it mentions 50 basis points and a basis point is "is equal to 1/100th of 1% or 0.01%", so for 50 bp 0.5% seems right.

50 basis points is 1/100th of a percentage point (pp), not a percentage (%).

What are you talking about? 50 basis points is 0,5%.

It can be. 50bp is always equivalent to 0.5pp, but only sometimes equivalent to 0.5%. A % increase is dependent on relative change. The increase from 0.25 to 0.75 talked about in the article, for example, is a 200% increase, a 0.5pp increase, and a 50bp increase. The difference between 0.75% and 0.25% is not represented as a %. That is now how % is calculated.

You did not define what your percentage applies to in your comment. Everyone here is talking about interest rate, not interest rate increase rate.

The topic of conversation here is how the European Central Bank increased rates by 0.5 percentage points, which may also be stated as 50 basis points as a percentage point is 1/100th of a basis point. The European Central Bank did not raise any of its rates by 0.5 percent. The previous commenter, among others, merely mixed up percent (%) and percentage point (pp), is all. It's a common mistake, editorialized headline included.