Trading Fees
Every trade on Juhus is charged a fee derived from a single formula. No hidden multipliers, no surprise rebates. Just probability, size, and your lifetime trading activity.
The formula
fee = α · C · P · (1 − P) · multiplierwhere multiplier = 1.4 − 0.1 · ⌊log₁₀(V)⌋
Valid for V ≥ 1. At V < 1, the multiplier is clamped to 1.4.
What each symbol means
| Symbol | Name | Description |
|---|---|---|
| α | Base rate | Adjustable fee lever applied uniformly. Example: 0.03 corresponds to a 3% ceiling before the probability and volume factors scale it down. |
| C | Shares purchased | Number of contracts bought in the transaction. The fee scales linearly with size. |
| P | Implied probability | Market probability of the outcome, expressed between 0 and 1. |
| P·(1−P) | Variance term | Peaks at 0.25 when P = 0.5 and approaches zero near certainty, so fees shrink as outcomes become lopsided. |
| V | Lifetime volume | Your cumulative trading volume on Juhus across every market you have ever traded. This is a per-user total, not a per-market figure. Every trade you make, on any market, pushes V upward for the rest of your account. |
| ⌊log₁₀(V)⌋ | Volume decade | Floor of the base-10 logarithm of your lifetime volume. Groups each user’s total activity into decades without any interpolation. |
How your lifetime volume discounts your fees
V is tracked per user across every market you have ever traded on Juhus. The more you trade over your account’s lifetime, the further down the bracket ladder you move and the lower your fee rate becomes. New traders start in the top bracket; highly active users graduate to the bottom bracket and stay there.
| Lifetime volume (V) | ⌊log₁₀(V)⌋ | Multiplier | Max rate (α = 3%, P = 0.5) |
|---|---|---|---|
| < 10 | 0 | 1.4 | 1.050% |
| 10 – 99 | 1 | 1.3 | 0.975% |
| 100 – 999 | 2 | 1.2 | 0.900% |
| 1,000 – 9,999 | 3 | 1.1 | 0.825% |
| 10,000 – 99,999 | 4 | 1.0 | 0.750% |
| 100,000 – 999,999 | 5 | 0.9 | 0.675% |
| 1,000,000+ | 6 | 0.8 | 0.600% |
Details worth knowing
A few properties of the formula that affect how it behaves in practice.
- Variance term
- P·(1−P) is the variance term. It peaks at P = 0.5 and approaches zero as outcomes approach certainty, so lopsided trades are charged proportionally less.
- Floor function
- The floor function keeps the multiplier flat within each bracket, with no interpolation between decades. A user with V = 99 pays the same multiplier as a user with V = 11.
- Base rate
- α scales every fee proportionally. Changing α shifts the whole curve up or down without altering its shape.
- No ceiling
- The formula extends indefinitely. Each additional power of 10 in your lifetime volume reduces your multiplier by another 0.1, a loyalty reward with no ceiling.