September 12, 2026

How much can you trust your TimeCost result?

The formula is simple. What matters is how completely you mapped your spending — data completeness, not math accuracy.

Data completeness and confidence — TimeCost
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The TimeCost formula is very simple. What is harder: how well do you actually know your spending? Enter rent, groceries, and a car but forget insurance, travel, subscriptions, clothes, maintenance, and annual bills — the calculator will perfectly compute… the wrong total. So we talk about input completeness, not “math accuracy.”

What drives result quality

Two users. One picks quick slider presets. The other opens their bank app and enters real housing, food, transport, and subscription amounts. Same formula. We trust the second result more. That is what the TimeCost completeness indicator shows.

Mostly presets 58%
Manual input in 3+ categories 88%

It does not mean “we know 88% of your financial life.” It means “you gave enough detail for a more useful result.” The cap is about 95% — we never claim to know every coffee or cash expense.

How to get a more realistic number

  1. Start with what you know exactly: rent or mortgage, utilities, phone, insurance.
  2. Check average food and transport over the last few months.
  3. Include non-monthly costs: annual insurance, vacation, car service, taxes, yearly subscriptions — spread over 12 months.
  4. Re-run after big life changes — move, child, new car, or rent jump matter more than a €4 coffee.

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Recalculate your TimeCost →