Just finished 5 days spending €247 including accommodation. Here's the breakdown:

Accommodation: €95 total (hostel in 10th arrondissement, 6-bed dorm)

Transport: €32 (Navigo weekly pass zones 1-5, covers everything including airport)

Food: €89 (street markets, supermarkets, 2 cheap restaurant meals)

Attractions: €31 (Louvre student rate €12, climbing Arc de Triomphe €13, rest free)

Key savings: stayed near République for easy metro access to everything, bought groceries at Franprix, used student ID everywhere possible, avoided anything in zones around major monuments. Ate lunch from markets, cooked hostel breakfast, one proper dinner per day average €12.

This isn't luxury but you see everything important and eat well if you shop smart.