How much money (£) will i need for 4 days in Paris?

You don't mention your ages As you are both from a EU country you can get in free at most attractions if yo are under 26. Food at your hotel can be very expensive breakfast can be 30 euros and more for one. But you can go to a neighborhood boulangerie and get by for 5-6 euros. Restaurants = it is a matter to ask in your hotel Prices can be similar as in the UK, but anything with a star will be terribly expensive.

A dinner meal for instance at a good restaurant in Paris might cost you 50/60 euros per head. Lunches are usually lights and cheaper - then you will want to do some shopping or bring back souvenirs from Paris, therefore I'd say 150 euros/pp. Some museums are free, but transports (tube, buses, taxis)) are not. Can't remember the exact costs as I don't live in Paris anymore but those details are on google.

I would take £ 120 per day - you want to see a lot of things.

Good question .. heard it's basic etiquette to tip the waiters there too