Mdex fees vary by product while gas and price impact shape total trading costs

Trade size and pool reserves change the output

For a given pool and trade direction, a larger input relative to reserves generally produces greater price impact on the output. The automated market maker, or AMM, connects reserve quantities with the exchange price. A trade changes those quantities, moving the effective price along the pool’s curve. Price impact reduces execution value without creating a separate payment to the platform. When a quote already reflects pool charges and reserve movement, adding those effects again overstates the cost.

Slippage concerns the difference between a quote and execution. Its tolerance sets an acceptable boundary; it doesn’t set the pool’s trading fee.

The historical swap percentage applied to trading volume

Under the historical AMM fee model, the percentage applied to the transaction’s trading volume, so it wasn’t a charge on an entire wallet balance. The MDEX LightPaper described a trading fee equal to 0.3% of transaction volume. In general, a proportional fee equals the applicable trading amount multiplied by the fee fraction. The deployment and pair determine which terms belong in that calculation. The BNB Chain referral update effective December 8, 2022 used a 0.2% trading fee for WBNB/USDT in its examples. It specified 0.3% for other rebate-eligible pairs.

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Fee allocation describes how the collected charge supports different purposes. Earlier arrangements directed portions toward rewards, liquidity providers or repurchases, with allocations changing between documented versions. Those internal shares aren’t extra percentages to add above the trader’s charge. A buyback allocation also doesn’t mean that the trader receives the amount earmarked for repurchasing MDX.

The historical order-book feature could match an unanswered limit order against the DEX. Its order-book label alone therefore didn’t establish a separate fee schedule.

Gas and token approvals add separate network costs

When an operation requires an on-chain transaction, network gas pays for execution separately from the fee that the trading pool charges. The amount depends on the work performed and the selected network’s fee model. The amount exchanged doesn’t alone determine the network charge.

Token spending permission

An ERC-20 allowance authorizes a specified spender to transfer that token from the owner’s account, up to the approved amount. It doesn’t itself perform the swap or collect its trading fee.

The allowance amount

A larger approval expands the amount that the spender may access. It doesn’t mean that this amount has already moved. Network gas pays for recording the permission.

The approval transaction

Where a separate on-chain approval is needed, its gas adds to the total cost. A sufficient existing allowance for that token and spender on the selected network can remove that particular step. Authorization and swapping remain distinct operations, even when an interface arranges them within one flow.

Does transaction mining make a swap free?

Only eligible trades earned MDX subsidies under the documented transaction-mining program, so the reward didn’t erase every swap’s gross costs or execution losses. A subsidy could offset some expense, depending on its amount and realizable value. The number of reward tokens alone doesn’t establish reimbursement in the asset used to pay costs. Comparing the two requires a common valuation basis.

Reward eligibility was selective: the historical program didn’t subsidize every trading pair. Liquidity mining rewarded eligible liquidity provider (LP) token stakes, which was a different activity from making a swap. A quoted staking yield therefore can’t serve as the rebate for an individual trade. Claiming or converting a reward can also involve network execution, reducing the amount ultimately available to offset trading expenses.

Cost exposure across trading, staking and transfers

Charges for token swaps, staking and perpetual contracts apply to their respective operations and assets. Bridge routes and perpetual contracts had separate launch terms. HECO entries refer to the historical deployment.

Liquidity earnings and withdrawals affect the net return

For a liquidity provider, trading fees can become income, while entering or leaving a position can require paid network execution on the relevant chain. The historical pool model retained trading-fee value in the pool, connecting that value with liquidity shares. LP rewards and the provider’s stake therefore need a different cost comparison from an ordinary swap. The amount supplied remains capital in the position; it isn’t itself a fee paid to the exchange.

Changes in the value withdrawn can reflect asset prices and the pool’s token mix. They don’t automatically reveal a withdrawal charge. Mining rewards also fluctuate with their token value and distribution terms. Net return compares the position’s value and earned rewards with committed capital and actual expenses. The reward token’s sale proceeds can differ from its valuation in an annualized yield display.

Perpetual trading had an MDX payment discount at launch

The October 10, 2022 ApolloX Finance integration introduced a futures-specific payment discount, separate from the AMM’s spot trading charge. At that launch, paying perpetual trading fees with MDX reduced those fees by 10%. This meant a reduction of the applicable fee, rather than ten percentage points off its rate. Opening and closing executions belong to the futures trading schedule. Funding transfers and forced-liquidation charges require separate treatment from an execution-fee discount. These launch terms don’t establish today’s maker or taker rates.

Funding payments and liquidation charges affect net returns

An open perpetual position could incur periodic funding, while forced liquidation created an additional charge under the documented ApolloX-based system.

Funding relative to position exposure

The documented funding amount equaled position notional value multiplied by the funding rate. Its base was exposure, not just the margin posted. Positive funding meant long traders paid shorts; negative funding reversed the direction. ApolloX transferred funding between users without a separate funding-transfer fee. Only positions open at settlement paid or received it. The historical schedule used 00:00, 08:00 and 16:00 UTC, with a possible 15-second timing deviation.

Charges after forced liquidation

The liquidation protocol assigned a portion of its fee to the insurance fund. Transaction history identified this as an Insurance Clearance Fee. This charge arose during forced liquidation, distinguishing it from an ordinary voluntary close. An execution-fee discount alone doesn’t establish a discount on the liquidation settlement charge.

Network status changes the cost comparison

The November 20, 2024 Mdex notice named January 15, 2025 as HECO’s scheduled shutdown date, limiting the relevance of older HECO fee claims. It also warned of clearance affecting certain HECO assets. That notice concerned HECO; it didn’t establish the status of every other deployment. Historical low gas costs don’t establish that the old network operation remains available. Likewise, a bridge relaunch announcement describes its stated routes and date, without setting a permanent transfer tariff.

For an available operation, compare the output and separately paid expenses on the same valuation basis. A same-network swap involves a different set of charges from moving MDX between networks first. The latter comparison must include transfer-related costs as well as any later trade. Comparing only swap percentages leaves that additional expense outside the total.