There is a simple rule of thumb equation that you can use to establish the level of debt that you can afford. Sum up all your monthly income and deduct all your monthly expenses. Divide the result by the debt you hold – loans and credit card balances to be included. If your debt level is between 21% and 35% you are exposed. If your debt level is over 36% – you are in trouble. Use our ĠEMMA My Debt Affordability Calculator to see the level of debt which you can afford at any point in time.