Scaling & units

You type $65,000. The chain can’t store that — it stores whole numbers only. So DeepBookie multiplies it up to a big integer, sends that, and converts it back for you. This page shows the math and the helpers that run it.

You rarely touch this. The app and the AI handle it. Read on if you’re building with the SDK.

Prices, strikes, and probabilities: ×1e9

These three are scaled by a constant called FLOAT_SCALING, which is 1_000_000_000 (1e9). To scale, you multiply:

$65,000 × 1e9 = 65,000,000,000,000

So a strike of $65,000 is stored on-chain as 65000000000000. A probability of 0.55 is stored as 550000000. To read a value back, you divide by 1e9.

dUSDC: 6 decimals

dUSDC is the settlement token. It has 6 decimals, so one dollar is 1_000_000 base units:

$1.50 × 1e6 = 1,500,000

This is a different scale from the ×1e9 fields above. Use the right divisor for each.

Strikes snap to a grid

You enter any dollar amount. DeepBookie snaps it to the nearest valid grid strike for that market automatically — markets only list strikes at fixed steps. So $64,950 may become $65,000. The receipt always shows the exact strike you’ll trade.

Timestamps: epoch milliseconds

Expiries and other timestamps are epoch milliseconds, matching Sui’s Clock. Pass them straight to new Date(ms) — no × 1000.

The four helpers

@deepbookie/predict-client ships one pair per scale. to* multiplies up for the chain; from* divides back for display.

import { fromScaled, toScaled, fromDusdc, toDusdc } from '@deepbookie/predict-client';
 
toScaled(0.55);          // 550000000n   (human number  -> ×1e9 bigint)
fromScaled(550_000_000); // 0.55         (×1e9 integer  -> human number)
 
toDusdc(1.5);            // 1500000n     (human dollars  -> 6dp bigint)
fromDusdc(1_500_000);    // 1.5          (6dp base units -> human dollars)

• toScaled / toDusdc take a human number and return a bigint for building a transaction.
• fromScaled / fromDusdc take a number | bigint and return a number for display.

Both to* helpers throw a RangeError on negative or non-finite input.

At a glance