Fees and limits

Fees

Seeryx fees explained with charts: the taker fee of 7% × p × (1 − p) per share, the 20% maker rebate, a calculator, and deposit and withdrawal fees.

Current rates

Taker fee rate—× p × (1 − p) per share

Maker rebate—of the taker's fee

Most per share—at 50¢

Smallest order—shares

Reading GET /api/fees... The formula: a taker pays shares × 7% × p × (1 − p), the maker gets 20% of it back.

Taker fee

The order that trades against a resting order, the taker, pays a fee on every fill:

fee=shares×7%×p×(1 − p)

p is the fill's price in dollars (45¢ is 0.45). The fee is in USDC, computed per fill and rounded down to a millionth of a dollar.
A buy pays it on top of the price; a sale has it taken from the proceeds. A market buy's amount includes it.
p × (1 − p) is largest at 50¢ and falls to almost nothing toward 0¢ and 100¢: the fee follows the uncertainty of the outcome, not the size of the price.
Resting (maker) orders pay no fee. Splits, merges and payouts pay none either.

The fee by price

Taker fee per share, in cents

Peaks at 50¢ with 1.75¢ a share; 0.069¢ at 1¢ and 99¢. Symmetric: a share at p pays the same fee as one at 100 − p.

Fee as a share of what a buy costs

Cheap shares carry the highest fee in relative terms: about 5.9% of the total at 10¢, 3.4% at 50¢, 0.7% at 90¢. On top of the price alone it is 7% × (1 − p).

Move the pointer over a chart, or focus it and use the arrow keys, to read a price.

Fee calculator

A buy of Up or Down shares, at the rates above. Prices follow the price grid: whole cents, and tenths of a cent below 1¢ and above 99¢.

SharesPrice (¢)

You are the

Your buy trades at once against a resting order.

Shares at the price: $50.00100 × 50¢
Taker fee: $1.753.5% of the price paid
Maker rebate: $0.00Only for the resting order
Total cost: $51.75

Payout if it wins: $100.00100 × $1.00
Profit if it wins: $48.25
Loss if it loses: −$51.75

Worked examples

100 shares bought at different prices.

Price	Shares cost	Taker fee	Fee on the price	Taker pays	Maker rebate
1¢	$1.00	$0.0693	6.93%	$1.0693	$0.01386
10¢	$10.00	$0.63	6.3%	$10.63	$0.126
25¢	$25.00	$1.3125	5.25%	$26.3125	$0.2625
50¢	$50.00	$1.75	3.5%	$51.75	$0.35
75¢	$75.00	$1.3125	1.75%	$76.3125	$0.2625
90¢	$90.00	$0.63	0.7%	$90.63	$0.126
99¢	$99.00	$0.0693	0.07%	$99.0693	$0.01386

At 50¢ the fee is 1.75¢ a share: 100 shares cost $50.00 plus $1.75, and the maker of that fill gets $0.35 back. If the shares win they pay $100.00.

The resting order of a fill, the maker, pays no fee and receives 20% of the taker's fee into its cash at the same moment. A resting buy filled at 50¢ for 100 shares costs $49.65 instead of $50.00. Post-only orders guarantee you are always the maker.

// micro-USDC, rounded down, exactly as the exchange computes it
const takerFee = (units: bigint, tenths: bigint, rateBps: bigint) => units * rateBps * tenths * (1000n - tenths) / 100_000_000n;
const makerRebate = (fee: bigint, rebateBps: bigint) => fee * rebateBps / 10_000n;

// 100 shares (1,000,000 units) at 50c (500 tenths), with GET /api/fees
const fee = takerFee(1_000_000n, 500n, 700n);   // 1750000n = $1.75
const rebate = makerRebate(fee, 2000n);        // 350000n = $0.35

Units are 1/10000 of a share, prices tenths of a cent, money micro-USDC.

Other fees

What	Fee	Field
Deposit (from your wallet or to your deposit address)	1 USDC per deposit by default, the rest is credited	`depositFee`
Immediate withdrawal	1 USDC by default, taken from the amount	`withdrawFee`
Delayed withdrawal	Free (it waits 60 seconds)	`withdrawDelay`
Split, merge and payouts	Free
Solana network fees and account rent	Paid by Seeryx: your wallet needs no SOL	`relayed`
Deposits and withdrawals on other networks	The bridge's own network cost, quoted before you confirm	`POST /api/withdraw/quote`

Fields of GET /api/funds; the defaults are shown until it answers.

Where fees show up

Order answers: spent and proceeds include the fee; a market order also answers fee.
Activity: each trade row has fee, positive for a fee you paid, negative for a rebate you received, and amount, the change of your cash with it.
P&L: GET /api/pnl returns fees.paid and fees.rebates for the period.
Signed orders: maxFeeBps caps the rate an order accepts; sign the current rateBps. See Signing orders.