Paying for the OpenAI API with Pix: what OpenAI accepts and how to use GPT paying in reais

OpenAI accepts Pix for ChatGPT, but not for API credits. Go, Plus and Pro plans bought on chatgpt.com can be paid with Pix and are charged in reais; API credits, bought on platform.openai.com, are sold only in US dollars (OpenAI help center, checked on October 10, 2026).

To call GPT models over the API and pay with Pix, the route is to top up a prepaid balance with Pix at Kunavo, an independent OpenAI-compatible gateway, and change only the base_url and the key in your code. The amount appears in reais on the Stripe checkout, the minimum top-up is $10, there is no monthly fee and the balance never expires. That balance pays for API calls: it does not pay for a ChatGPT subscription and does not become credit in an OpenAI account. Prices and payment methods checked on October 10, 2026.

Short answer: where Pix works and where it does not

• ChatGPT on the web (chatgpt.com): Pix, yes. OpenAI's page on multi-currency billing says that in Brazil Pix is accepted for the Go, Plus and Pro plans, and lists the real among the subscription currencies. Credit and debit cards work in every country (OpenAI help center, checked on October 10, 2026).
• ChatGPT in the iPhone or Android app: the store bills you. The same page notes that if you subscribe in the app, the subscription is managed by the App Store or Google Play and charged in local currency. The stores' payment methods in Brazil were not checked here.
• API credits on platform.openai.com: Pix, no. API credits are bought in US dollars only (same page), and for them OpenAI accepts only a standard credit or debit card; a prepaid card will not do (article on declined cards, checked on October 3, 2026).
• GPT over the API, through Kunavo: Pix, yes. For payers in Brazil, Kunavo's Stripe checkout shows the amount in reais and offers Pix. You pay Kunavo, not OpenAI: the balance calls GPT models, and Claude models too, with a Kunavo key, and usage is billed per token.

OpenAI also explains that ChatGPT and the API platform have separate billing systems (OpenAI help center, checked on October 3, 2026). So a Plus plan paid with Pix includes no API usage, and a Kunavo balance, for its part, does not work inside ChatGPT.

Buying credits directly from OpenAI: what to know

If you have a card that OpenAI accepts, you can buy credits directly from OpenAI, and the minimum there is lower than Kunavo's. The rules, according to OpenAI's help center (checked on October 3, 2026):

• the minimum purchase is $5 and the default amount is $10 (prepaid API billing);
• auto-reload is switched on by default during setup, and you have to turn it off if you do not want it;
• purchased credits expire after one year and are non-refundable, except where law or contract requires otherwise or an exception is approved (same page);
• when you change the API payment method, a temporary $5 charge may appear, reversed within 7 days (article on the temporary authorization);
• when a card is declined, OpenAI points, besides prepaid cards, to banks that block online or international purchases by default and to an unfinished 3D Secure check (article on declined cards).

The GPT models a Pix-funded balance can call

Kunavo is an independent gateway: it is not OpenAI and not an OpenAI partner. Its API is compatible with OpenAI's (and with Anthropic's), so the same key and the same balance call the GPT models below and the Claude models, billed per token. Prices in US dollars per 1M tokens; the right-hand column is what OpenAI charges today (OpenAI API pricing, checked on October 10, 2026).

On output, these models cost between 60% and 65% less at Kunavo than OpenAI's regular price, not counting promotions.

OpenAI charges a promotional $4,00 / $20,00 for GPT-5.6 Sol at least through November 21, 2026; its regular price is $5,00 / $30,00.

Even against the promotional price, output on GPT-5.6 Sol costs about 40% less at Kunavo.

Models that are paused at Kunavo are not listed. Every price is on the pricing page.

From Pix to GPT's first answer

1. Account. Sign up with an email address or a Google account. No payment details are asked for until you decide to top up.
2. Amount. In Billing, choose how much to top up, from $10. Amounts are in US dollars, like the per-token rates; the equivalent in reais appears on the next screen.
3. Checkout in reais. For payers in Brazil, Stripe's payment page opens in reais, and only then does Pix appear among the options (Stripe's Pix documentation), next to card, Link and, if they are set up on the device, Apple Pay or Google Pay.
4. Payment in your banking app. Choose Pix, scan the QR code or copy the Pix code (the “copia e cola”) and confirm in your banking app. In the app, the payee appears as Ebanx, Stripe's Pix partner, and the selling company's name goes in the identification field (Stripe).
5. Balance. Stripe receives the confirmation as soon as the Pix is paid (Stripe), and Kunavo credits the balance only after that. If the amount has not appeared in Billing yet, refresh the page before paying again: a second Pix does not fix the first one, it becomes another top-up.
6. Key. In API Keys, create a key that starts with sk-kn-. It is shown in full only once; store it in an environment variable or a secrets manager before you close the window.

To check that everything works, a call to GPT-6 Sol from the terminal:

# Teste rápido: se responder, a chave e o saldo estão funcionando.
curl https://api.kunavo.com/v1/chat/completions \
  -H "Authorization: Bearer $KUNAVO_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-6-sol",
    "messages": [{"role": "user", "content": "Responda em uma linha: tudo certo?"}]
  }'

In projects that already use the openai library for Python, nothing changes except the key and the endpoint:

# O SDK da OpenAI que você já usa, apontado para a Kunavo.
from openai import OpenAI

client = OpenAI(
    api_key="sk-kn-...",                    # chave da Kunavo, não a da OpenAI
    base_url="https://api.kunavo.com/v1",   # endpoint compatível com a OpenAI
)

resp = client.chat.completions.create(
    model="gpt-6-sol",
    messages=[{"role": "user", "content": "Olá do Brasil!"}],
)
print(resp.choices[0].message.content)

For Codex CLI, the setup is in the guide to Codex CLI with an API key.

What it costs in reais

Kunavo's prices are in US dollars. Stripe converts them to reais, and the exchange rate it applies includes a 2–4% conversion fee paid by the buyer; the rate is guaranteed for 24 hours (Stripe, Adaptive Pricing, checked on October 10, 2026). Since Pix exists only in reais, paying with Pix always means paying that fee. Paying in dollars by card avoids it, but then your bank's exchange rate and fees apply.

IOF comes on top. According to Stripe's Pix documentation, IOF (Brazil's tax on financial transactions) applies to transactions that involve currency exchange, such as reais to dollars, and is charged to customers in Brazil who pay businesses outside the country; the rate it gives is 3,5%. Under the default setting, which Kunavo's checkout does not change, the customer pays it, and the banking app shows the amount with the IOF added (Stripe, Pix, checked on October 10, 2026).

An example, token arithmetic only: a chat request with 1.000 input tokens and 300 output tokens costs about $0,002 on GPT-6 Sol ($0,80 / $4,00 per 1M tokens), so the $10 minimum top-up covers about 5.000 requests of that kind. At the price OpenAI charges today for GPT-6 Sol, the same request costs about $0,005. The conversion fee and the IOF are added to the amount in reais that you pay; they do not come out of the dollar balance. Real spending depends on the length of prompts and answers, and on caching.

Larger top-ups come with a balance bonus:

• $100 → $110
• $1.000 → $1.200
• $5.000 → $6.250

Before you pay: Pix limits

• Up to US$ 3.000 per Pix. Stripe accepts a Pix of at least R$ 0,50 and at most US$ 3.000 (Stripe, Pix). The $5.000 top-up is over that cap and has to be paid by card.
• Pay within the hour. The payment page Kunavo opens expires one hour after it is created, and an expired Pix can no longer be paid (Stripe, Pix in Checkout). If that happens, go back to Billing and start a new top-up.
• Top-ups are always manual. Kunavo's auto-recharge, which kicks in when the balance falls below a threshold you set, charges only a saved card or Link. Stripe has Pix Automático for recurring charges, but Kunavo does not use it: with Pix, you make each top-up yourself, when you need it.
• No nota fiscal. Kunavo issues no nota fiscal (the Brazilian tax invoice) and no invoice of any other kind. Billing keeps the top-up history, with date, amount and status.
• Refunds. They are reviewed case by case and, by default, come back as balance credit; a refund to the bank account, through Stripe, is made on request (billing policy). On Stripe's side, a Pix payment can be refunded up to 90 days later (Stripe, Pix).
• No Boleto or PayPal. Neither is offered at Kunavo's checkout.
• It is the API, not ChatGPT. The balance pays for GPT and Claude API calls. It does not become a ChatGPT subscription and does not show up as credit on platform.openai.com.

See also

For Claude and Claude Code on the same balance, see how to pay for Claude with Pix. The cost of each GPT model in real requests is in OpenAI API pricing. And for Portugal, the same question with MB WAY is answered in paying for the OpenAI API with MB WAY, in European Portuguese.

To try it now, create your account: $10 paid with Pix is enough balance to put GPT-6 Sol to the test in your own code.

Frequently asked questions