How can one who used the internet—thinking its owner was content—give charity when he does not remember the duration of his usage or the price of the internet, and is the charity immediately obligatory, and to whom should it be paid?

Whoever owes a right but does not know its exact amount, and cannot ascertain its measure, should strive to pay what he believes most likely clears his obligation. If he hesitates between two amounts, he should pay the higher one to clear his conscience.

He should donate that right as charity on behalf of its unknown owner or one who cannot be reached. As Sheikh Al-Islam Ibn Taymiyyah said: "Money whose owner is unknown to us is no longer obligatory for us to return to him. It should be spent on the welfare of Muslims, and charity is one of the greatest forms of Muslim welfare. This is a general principle for all money whose owner is unknown, making it impossible to return it to him; such as usurped property, borrowed items, and deposits. These are spent on the welfare of Muslims according to the madhhab of Malik, Ahmad, Abu Hanifa, and others."

It is obligatory to seek forgiveness for this injustice and others, when possible, based on the hadith: "On the hand is what it took until it returns it." The absence of a password for a network owned by another does not permit benefiting from it without the owner's permission. A person's failure to secure his property does not permit aggression against it.