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Size your startup raise by milestones

Raise enough runway to hit the milestones that unlock your next round, not a round number that sounds impressive. Work backward from what you must prove and what it costs.

Updated Aug 5, 2026 ·
Size your startup raise by milestones

Why this matters

"$1M, because that's what seed rounds are" is how founders end up either out of money before proving anything or over-diluted with burn creep. The right raise is sized backward from a milestone, not picked from a round-number menu.

What "done" looks like

  • The milestone that makes you fundable at a higher price is written down
  • A monthly cost model shows what reaching it takes
  • Your number covers a context-appropriate runway, often 18 to 24 months, with a buffer
  • You can defend the amount and the dilution it implies in one minute

How to do it

  1. Name the next fundable milestone, the proof point that justifies a better valuation, not "more runway."
  2. Budget the monthly burn to reach it: people, tools, marketing.
  3. Multiply by the months required, then add an appropriate buffer, often 25 to 50%. Everything slips.
  4. Sanity-check runway: 18 to 24 months is a common benchmark, depending on the company and market, so you aren't fundraising again in nine.
  5. Check the dilution: selling 20 to 25% can be a useful early-round benchmark, but the right level depends on the company and deal. More dilution affects your cap table for every round after.
  6. State a defensible range, not a single magic number.

Common mistakes

  • Copying a peer's round size, their milestone isn't yours
  • Sizing to survival ("we need cash") instead of to proof
  • Assuming a top-up will be easy later; bridge rounds are hardest exactly when milestones slip

Real-world examples

  • Y Combinator's published fundraising advice frames the amount the same way: months of runway times burn, aimed at a milestone that unlocks the next round.
  • Paul Graham's essay "Default Alive or Default Dead?" offers a related test: know whether current numbers reach profitability before the money runs out.

From a founder's point of view

The size of this raise sets the difficulty of the next one. A modest round fully deployed against a clear milestone beats a big round absorbed by payroll. Dilution is forever; the buffer is negotiable; the milestone is the point.

Rule of thumb

Your number should equal monthly burn × months to milestone, plus buffer. If it didn't come from that arithmetic, it isn't your number.

Our guides are researched and reviewed from multiple angles, including AI tools, primary sources, and experienced founders. They are general information, not professional advice. Please verify important details yourself or with a qualified professional.

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