Burn rate is the trailing 30-day expense total. It is the input almost every other planning figure depends on, because runway, emergency fund sizing and retirement targets are all denominated in months of spending rather than in dollars.
A single month is a noisy estimate. Large irregular items such as an annual insurance premium or a car repair land in whichever month they happen to fall, and they move a 30-day figure enough to make it misleading.
The six-month average is the more stable measure, and the gap between the two is itself informative. A 30-day figure persistently above the six-month average means the recent months are not anomalies any more.
Worked through
Six-month average against reserves
Denver household, expenses averaged over six months to smooth out irregular items.
- Rent
- $1,650
- Everything else
- $2,550
- Burn rate
- $4,200/mo
- Runway on $18k
- 4.3 months
Six months at this burn rate is $25,200. Reserves of $18,000 cover 4.3 of those months.
Where this lives in Promi
Cash Flow page. Trailing 30-day burn rate, updated daily.
Related in Cash Flow & Runway
See your own burn rate
Promi computes this from your linked accounts, with the definition one click from the number.
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