Oh Ventures
Tools · Tool 01

SAFE Modeler.

SAFE conversion math, run the way an institutional investor will run it.

A founder-side model. Layer in your cap table, your outstanding SAFEs, and a hypothetical priced round. See the conversion price each SAFE produces, the mechanism that wins (cap, discount, neither), the resulting price per share, and the final ownership at close.

Founders & early holders

01

Outstanding SAFEs

02

Post-money SAFEs (YC 2018+ standard). Each SAFE's ownership locks in at amount ÷ effective cap, where effective cap = the lower of the stated cap or the discounted post-money valuation.

Next priced round

03

The pool refresh comes out of pre-money. Set to 0 to skip.

Round metrics

Live
Price per share
$0.0000
Post-money valuation
$0
Round investor %
0%

Ownership at close

Cap table

Holder Shares Ownership

SAFE conversion detail

Show the math

Sources & references

Conversion math sources
  • Y Combinator: SAFE Financing Documents The official YC SAFE templates (post-money valuation cap, post-money discount, post-money MFN, post-money cap and discount). The source of truth for SAFE structure. Primary instrument source
  • Y Combinator: Post-Money SAFE Primer (PDF) YC's own walkthrough of post-money SAFE mechanics: how ownership is locked in, how conversion works at the priced round, and where founder dilution lands. Conversion mechanics
  • Carta: State of Pre-Seed 2025 61% of 2025 pre-seed SAFEs use the post-money cap-only structure modeled by this tool. Pre-seed cap medians by round size are also published here. Market structure data
  • Qubit Capital: How Post-Money SAFEs Affect Founder Dilution Worked example of how post-money SAFE ownership stacks across multiple rounds and why founders consistently underestimate the conversion math. Dilution explainer

Engine note: this tool implements the post-money SAFE mechanics described in YC's primer. Pre-money SAFEs and MFN clauses are deliberately out of scope for the public model and handled inside Oh Ventures engagements where the cap table system has full context.

Companion reading

SAFE vs. priced round: how founders should decide.

The framework, the conversion math founders consistently underestimate, and when each instrument is the right call.

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Working through a real round?

The model is one input. The strategy is the engagement.

If you are running a real conversion conversation, we install the cap table architecture and run the math at every term sheet, every counter, every close.

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