Add up what you own and subtract what you owe to get a simple net worth figure in pounds. Use current balances rather than monthly payments so the result reflects your actual position today.
Examples: premium bonds, crypto, jewellery, business cash or anything you could reasonably sell.
Use remaining balances only. If a debt is joint, enter just your share if that is how you track your finances.
A single number is only a snapshot. Recheck every few months to see whether savings, investment growth and debt paydown are moving in the right direction.