There is no law regulating who you can date, only with whom you can have sexual relations.
Is it okay for a 17 year old to date a 25-year-old?
There is absolutely no illegality when a 25-year-old dates a 17-year-old.
Can a 26 year old date a 17 year old UK?
In the UK there is no law stating it is illegal for a 23 year old to date a 17 year old. As you are 17 and a young adult, you are old enough to decide if you want to be in a relationship with this man. Its important that both partners consent to the relationship, and that they trust and respect one another.
What age gap is too big for dating?
This rule states that by dividing your own age by two and then adding seven you can find the socially acceptable minimum age of anyone you want to date. So if youre a 24-year-old, you can feel free to be with anyone who is at least 19 (12 + 7) but not someone who is 18.