If you're viewing this page, you're probably getting this error while sending ADA: "Cardano network requires keeping minimum 1 ADA on the balance". Let's look at why it happened and solve it.

Cardano is a UTXO-based currency. But what is UTXO? 

UTXO is an abbreviation for Unspent Transaction Output. In the ADA network, your balance is not one value, but a sum of smaller values called UTXO. Each UTXO added to a transaction increases the size of the transaction, and consequently, the fee for that transaction. One UTXO can only be used in one transaction and it’s not possible to split a single UTXO into multiple recipients of a transaction.

If you have less than 1 ADA left on your balance, such a UTXO may be recognized by the network as dust, in which case it will be impossible to send it, so you need to keep at least 1 coin on your balance when sending not the whole balance.

What is dust?

Dust is a tiny amount of coins or tokens that is less than the network's fee for sending it. It's almost impossible to spend that amount. It's impossible to spend that amount. 

Therefore, you can't send funds if after the transaction you have UTXO less than 1 ADA (the minimum required amount).

What should I do?

Just change sending amount and try again!

For more information on this, you can read this article.