Paying for AI without a fee: is it possible and how to calculate the overpayment

The query "paying for AI without a fee" is understandable: nobody wants to give away extra percent. The honest answer is unpleasant: there is almost always a fee. It can be explicit, a line on the payment page, or hidden, in the exchange rate or the network charge. The task is not to find a fee-free method but to calculate what you really pay and pick the cheapest path. Below are formulas and examples for Zukko; for other services the approach is the same, take the numbers from them.

The fee data is as of October 18, 2026. It may change, so always check the final amount on the payment page before confirming.

Where the fee comes from

Between your rubles and the model's tokens there are several links, and each takes its share:

1. The payment channel. SBP, a bank card or a crypto transfer: each has its own processing cost.
2. Conversion. The balance is kept in dollars, while you usually pay in rubles. The exchange rate and the gap between the buy rate and the "market" rate is a cost too.
3. The network (for crypto). A stablecoin transfer is paid for with a network fee, charged by your wallet or exchange.

When something says "no fee", it usually means the fee is built into the rate or the price. The question is not "is there a fee" but "how much did you give up in total".

What is known about Zukko payment methods

Top-ups start from $1. More on each method: SBP: payment step by step↗, MasterCard↗, paying with crypto↗.

The formula: how many rubles for N dollars

For SBP:

where N is the top-up amount in dollars, rate is rubles per dollar at the time of payment, and 1.085 is the coefficient for the 8.5% fee. The reverse question (how many dollars you get for X rubles):

For MasterCard the coefficient is about 1.13 (a fee of about 13%; the payment page shows the exact amount to pay); for crypto, count by the final amount on the payment page.

An example with a hypothetical rate

The rate changes daily, so take a hypothetical 80 rubles per $1. It is not a forecast and not today's rate; plug in yours.

For the reverse question: 1000 rubles at the same rate gives 1000 / (80 × 1.085) = 1000 / 86.8 ≈ $11.52.

The same calculation in code, so you can plug in your own rate:

def rub_for_balance(usd: float, rate: float, fee: float = 0.085) -> float:
    return usd * rate * (1 + fee)

def balance_for_rub(rub: float, rate: float, fee: float = 0.085) -> float:
    return rub / (rate * (1 + fee))

print(round(rub_for_balance(10, 80), 2))    # 868.0
print(round(balance_for_rub(1000, 80), 2))  # 11.52

What the fee does to the token price

It is convenient to move the fee onto the price: multiply the model's rate by the method coefficient. Zukko prices as of October 18, 2026, $ per 1M tokens:

The main thing is visible: the fee changes the price by 8.5–13%, while the choice of model changes it severalfold. If spend is noticeable, you will save more by matching the model to the task than by changing the payment method. Current list and prices: GET https://api.zukko.pro/v1/models or the "Models" page in the dashboard.

How not to overpay

1. Compare methods on your own amount. With 8.5% against about 13%, the difference on $100 is around $4.50 in dollar terms. For small sums it is unnoticeable, for regular large top-ups it is already tangible.
2. Top up for real spend. There is no need to put "a year ahead" on the balance, since rates and conditions may change. Estimate a month or two of spend: tokens × the model price for each kind of request.
3. Mind the rate on the payment day. The balance is in dollars, so the ruble cost of tokens floats with the exchange rate. It is not a fee, but it affects the total.
4. For crypto, count the whole chain. The transfer amount plus the network fee plus the buy-rate difference of the stablecoin. If you already hold a stablecoin, the transfer is cheaper than buying one for this purpose.
5. Use the one-time bonus. Subscribing to the @zukkopro↗ channel gives $0.50, once per Telegram account: link Telegram in the dashboard, subscribe, press "Check". There is also a referral program: 10% of invited users' top-ups.
6. Check the amount before paying. The total is always visible on the payment page; compare it with your calculation.

The bonus and the 10% referral share do not cancel the fee, they only soften it a little. Nothing is "free" anywhere, and that is fine: what matters is that the calculation is clear.

How to check that it adds up

After a top-up open the dashboard and compare the credited dollar amount with the one you requested. Balance and spend are also available through the API (GET /v1/balance and GET /v1/usage). If a payment hangs or the amount does not match, see what to do if a payment hangs↗.

To start, create a key in the dashboard and top up the minimum amount: that way you test the whole path for a small sum.

FAQ

Is paying for AI in rubles without a fee possible?

Practically no: rubles have to be converted, and the payment channel charges. Sometimes the charge is hidden in the rate. Compare not the words "no fee" but the final amount in rubles per one dollar of balance.

Which is the cheapest way to pay for AI in Russia?

Of what we know: SBP with an 8.5% fee is cheaper than MasterCard with about 13%. For crypto the total depends on your exchange and network; count it from the payment page. Access from Russia is through the gateway, with payment by SBP, MasterCard or crypto.

Is the fee taken from the balance or added on top?

With SBP the 8.5% fee is added on top of the payment amount, and the balance is credited with the dollar amount you requested. You pay more, but the balance arrives in full.

Why do I need a different number of rubles for the same balance?

Because the rate at the time of payment differs. The balance is counted in dollars, and rubles are converted at the market rate at the time of payment.