Je tu Wi-Fi zdarma?
When to use
Use this question when you enter a cafe, restaurant, or hotel and want to know if they offer complimentary Wi-Fi before you commit to ordering or staying.
How it works
The phrase means 'Is there Wi-Fi for free?'. 'Je tu' - Is here / Is there 'Wi-Fi' - Wi-Fi 'zdarma' - for free, free of charge.
Grammar
The word 'zdarma' functions as an adverb here, indicating the manner in which the Wi-Fi is offered. It doesn't change based on gender or number.
Notes
Ask if free Wi-Fi is available before sitting down or buying something.