Level 3 · Breathing room
Flex budget calculator: how much is really free this month?
Fixed costs, reserve and savings come off first — what is left is genuinely free. Enter your four numbers and see how much you have available this month and per day.
Rent, utilities, insurance, subscriptions, instalments – everything that leaves regularly at a similar amount.
Provision for the irregular: repairs, annual fees, gifts.
The sum of your savings goals – deliberately before spending.
Spendable = income − fixed costs − reserve − savings. The pace value assumes 30 days per month.
Your inputs stay in your browser. Nothing is stored or transmitted.
How to go about it
- Enter your net income. What actually lands in your account each month — salary, side income, regular inflows.
- Subtract fixed costs. Rent, utilities, insurance, subscriptions, instalments — everything that goes out regularly in a similar amount. This number has to be right, or nothing else is.
- Subtract reserve and savings. A reserve for irregular costs (repairs, annual fees) and the sum of your savings goals — deliberately before spending, not after.
- Read the pace. The calculator shows what is free per day and what would have been free up to today — the pace marker for the current month.
Frequently asked questions
What is flex budgeting?
Instead of managing every category in its own pot, you form a single number: income minus fixed costs minus reserve minus savings. The rest is freely available — with no rule for what it is spent on.
Why does saving come off before spending?
Because saving whatever is left at the end of the month usually does not happen. Deducted first, the savings rate no longer competes with every impulse purchase — and the free number becomes a permission, not a ban.
What belongs in the reserve?
Everything irregular that still comes for sure: repairs, annual fees, presents, the dentist. As a rule of thumb five to ten percent of net income, more if your income fluctuates.
What if the number is negative?
Then your committed spending exceeds your income — the month ends in the red, however frugal you are day to day. The first lever is fixed costs, because they act every month.
Related
This is exactly the number sum calculates for you every month
Recurring items and subscriptions are detected automatically and can be corrected, the reserve and the rates of your goals come off first, and a pace marker shows whether you are on track for the rest of the month. You do not have to maintain a pot per category. Today you bring your transactions in via CSV import; the automatic bank connection (PSD2) is in the works.
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