Trade & profit-share outcome
On a loss you keep 100% of what's left and pay nothing. On a win, the "keep %" scales with your ROI — the more you win, the more you keep — between a 75% floor and a 95% ceiling.
Compare vs a flat round-trip fee venue
Most venues charge this fee on the full notional (collateral × leverage) whether you win or lose. Enter a comparable round-trip rate to see which model is cheaper for this specific trade.
A performance fee, not a transaction fee
Avantis' Upside Perps is a structurally different fee model from every maker/taker or flat open/close fee on this site — the protocol only gets paid when you do. Compare the discount-for-lock-up tradeoff on Hyperliquid's HYPE staking tiers, the routing-side fee/slippage tradeoff on the perp DEX best execution calculator, a time-decay carry fee on Ostium's rollover fee, or how a bad funding regime erodes a position on the funding rate pain calculator.
The math
Price move is m = (exit − entry) / entry for a long, or its negative for a short. ROI on collateral is ROI = m × leverage, and gross PnL is collateral × ROI. If gross PnL ≤ 0, the fee is $0 and the trader keeps the full (negative) result — Upside Perps take nothing from a loss. If gross PnL > 0, this calculator reconstructs Avantis' published keep-percentage curve from its two public anchor points — 75% kept at 100% ROI and 80% kept at 500% ROI — as a straight line with slope (80−75)/(500−100) = 0.0125 percentage points of keep per percentage point of ROI above 100%, clamped between the documented 75% floor and 95% ceiling. If the AVNT staking discount is applied, the fee portion (100% − keep%) is cut by roughly 25% before being subtracted from gross profit, per Avantis' staking-discount documentation.
This is our own linear reconstruction of two published examples, not an official Avantis formula — Avantis has not published the full ROI-to-keep table, only the two anchor points and the 75%/95% band they sit inside. Funding between longs and shorts, and the small positive-slippage rebate for trades that reduce open-interest skew, are separate from this fee and are not modelled here. The flat-fee comparison applies your entered round-trip percentage to the full notional (collateral × leverage) regardless of outcome, which is how maker/taker and flat open/close fees work everywhere else on this site — the point of the comparison is to show that the two models can flip which is cheaper depending purely on whether the trade wins or loses, not on its size.