The Burn Rate Report THEBURNRATEREPORT.COM
Issue 01 . startup treasury

Money leaves faster than anyone plans for

Flat runway arithmetic is the most comfortable wrong number in startup finance. Scroll and watch what the growth term does to a balance that felt safe on Monday.

Runway you think you have
18.9
months, before the burn grows
Scroll
Stage 01 of 06

A company with 1.8 million in the bank

Scroll and the months run forward. The line is the cash left in the account at the end of each month, and it starts at one point eight million with nothing spent yet.

    Cash left in the account, month by month Starting balance $1.80m, net burn $95k in month one, burn growing four per cent every month. Scrolling this section moves you forward through the months.
    Burn that grows The flat formula
    Months since the round closed
    Month
    0
    Since the money landed
    Cash left
    $1.80m
    End of that month
    Runway still ahead
    14.4
    Months, at the burn by then
    When a limit or a rate here changes, you hear it from us

    Insurance limits, sweep terms and card underwriting rules all move, and the version in your head is usually the version from the last time you looked. One line per change, with the figure before and after.

    One address, no list swaps, and nothing is sent unless a figure on this site actually changed. This is our own reading of public sources and not advice on your own situation.
    What the growth term costs
    0Runway the flat formula invents at four percent monthly burn growth
    0Bank failures since January 2023 out of 4,255 insured institutions
    0FDIC coverage for each owner at each bank in each category
    Run it on your own numbers

    Six inputs, any numbers you like

    Type your own figures. No sliders with a floor on them, because a company with 40,000 dollars in the bank has the same question as one with four million and deserves the same answer.

    $
    $
    $
    %
    %
    $
    #
    $
    #
    Runway
    0
    months until the balance hits zero
    Flat formula says
    0
    cash divided by today's net burn
    The gap
    0
    months the flat number invents
    Net burn now
    0
    spend minus revenue, this month

    Where the four per cent comes from, since everybody asks

    Spend growth is the term the flat formula drops, and four per cent a month is not a guess. It is what a normal quarter does to a 120,000 dollar cost base. Here it is taken apart.

    One senior hire a quarter, 180,000 a year fully loaded+$5,000/mo4.2%
    Cloud and usage bills rising with your own traffic+$900/mo0.8%
    Software seats added one at a time as people join+$400/mo0.3%
    Annual pay review, spread across twelve months+$600/mo0.5%
    Things you cancel, minus what you renegotiate-$1,100/mo-0.9%
    What that adds up to4.9%

    So four per cent is on the low side, not the high side. And you do not have to trust our decomposition at all, because your own books already answer it. Put in what you spent twelve months ago and what you spend now, and the box below works out your actual rate.

    $
    $
    %

    The arithmetic is the twelfth root of now divided by then, minus one. Nothing clever. If that number is higher than the one you typed into the model above, the model above is optimistic and you should go and change it.

    This is a model. Not financial advice, and we hold no licence to give any. Anything here should go past your accountant and your board before it goes anywhere near a bank.
    Our own model. The same arithmetic runs inside the article. FDIC and Delaware figures pulled 29 Jul 2026 . method

    The reading

    All of it
    BR
    the treasury desk

    One desk, working from filings and public data rather than from vendor decks. Models are published with their assumptions attached, so you can disagree with the assumption rather than with the number.