# MarginPad

> Free crypto futures calculators and a free JSON API. Everything runs in the browser, no signup, 12 languages. Calculations: liquidation price, risk-based position size, PnL/ROI/ROE, dollar-cost-average entry, take-profit ladder, and risk/reward. Works alongside Bybit, Binance, OKX, KuCoin, Gate and Kraken.

## Calculators
- [Liquidation price](https://marginpad.io/#liq): isolated-margin estimate = Entry × (1 − 1/Leverage + MMR) for a long, Entry × (1 + 1/Leverage − MMR) for a short.
- [Position size](https://marginpad.io/#size): risk-based; size = (balance × risk%) ÷ |entry − stop|.
- [PnL / ROI / ROE](https://marginpad.io/#pnl): ROE = price ROI × leverage.
- [DCA / average entry](https://marginpad.io/#dca): average = total cost ÷ total quantity.
- [Take-profit ladder](https://marginpad.io/#tp): exit = Entry × (1 ± ROE / (100 × Leverage)).
- [Risk/reward](https://marginpad.io/#rr): ratio = reward ÷ risk; break-even win rate = risk ÷ (risk + reward).

## API (free, JSON, no key, CORS)
- [API documentation](https://marginpad.io/api/)
- GET https://marginpad.io/api/liquidation?entry=60000&leverage=10&side=long
- GET https://marginpad.io/api/position-size?balance=5000&risk=1&entry=60000&stop=58800
- GET https://marginpad.io/api/pnl?entry=60000&exit=66000&size=0.5&leverage=10
- GET https://marginpad.io/api/risk-reward?entry=60000&stop=58000&tp=66000
- GET https://marginpad.io/api/take-profit?entry=60000&leverage=10&roe=75

## Per-exchange calculators
- Liquidation: [Bybit](https://marginpad.io/bybit-liquidation-calculator/), [Binance](https://marginpad.io/binance-liquidation-calculator/), [OKX](https://marginpad.io/okx-liquidation-calculator/), [KuCoin](https://marginpad.io/kucoin-liquidation-calculator/), [Gate](https://marginpad.io/gate-liquidation-calculator/), [Kraken](https://marginpad.io/kraken-liquidation-calculator/)
- PnL: same six exchanges at /{exchange}-pnl-calculator/

## Guides
- [What is liquidation in crypto](https://marginpad.io/blog/what-is-liquidation-in-crypto/)
- [How to calculate liquidation price](https://marginpad.io/blog/how-to-calculate-liquidation-price/)
- [Crypto position sizing (1% rule)](https://marginpad.io/blog/crypto-position-sizing-risk-management/)
- [Cross vs isolated margin](https://marginpad.io/blog/cross-vs-isolated-margin/)
- [Crypto leverage explained](https://marginpad.io/blog/crypto-leverage-explained/)
- [What is funding rate](https://marginpad.io/blog/what-is-funding-rate/)
- [Risk/reward ratio explained](https://marginpad.io/blog/risk-reward-ratio-explained/)
- [Full blog index](https://marginpad.io/blog/)

## Key facts
- Liquidation distance from entry ≈ 1/leverage minus maintenance margin: 10x ≈ 9–10%, 25x ≈ 4%, 100x ≈ 1%.
- A 6% price move at 10x leverage ≈ 60% return on equity (ROE).
- Break-even win rate by risk/reward: 1:1 = 50%, 2:1 ≈ 33%, 3:1 = 25%.
- MarginPad is an educational tool, not financial advice. Figures exclude fees and funding.