What Is OpenAI API Billing
The OpenAI API is the programmatic interface developers use to connect GPT-4o, Whisper, DALL-E, and other OpenAI models to their applications. Unlike ChatGPT Plus (a fixed subscription), the API uses a pay-as-you-go model: you pay for each token consumed. To get started, you need to add a payment method and load credits.
Which Cards Work with OpenAI API
OpenAI API uses Stripe and accepts:
- Visa and Mastercard — debit and credit cards
- American Express — in supported regions
- Does not accept: Mir, UnionPay, cards from Russian banks, prepaid cards
Virtual cards with a debit BIN (not prepaid) work perfectly. This is exactly the type of card Marix issues.
Step-by-Step: Setting Up OpenAI API Billing
Step 1. Register or sign in at platform.openai.com.
Step 2. Go to Settings → Billing. The billing section shows your current balance and the option to add a payment method.
Step 3. Click "Add payment method." You'll be redirected to a Stripe form.
Step 4. Enable a VPN with an IP in the card's country (US or Europe).
Step 5. Enter your virtual card details:
- Card number
- Expiry date (MM/YY)
- CVV
- Cardholder name (as it appears on the card)
- Billing address (in the card's country)
Step 6. Confirm the card. Stripe will make a $0 or $1 test charge (immediately reversed) to verify the card.
Step 7. Add credits. After adding the card, go to "Add credit" and choose an amount. Minimum is typically $5–$10.
Step 8. Set up auto-recharge (optional). In the "Auto recharge" section, configure automatic top-ups when the balance falls below a threshold.
Usage Tiers and Limits
OpenAI API sets rate limits based on usage tier:
- Tier 1 ($5+ in account): base limits
- Tier 2 ($50+ spent): higher limits
- Tier 3 ($100+ spent): even higher
The more you spend, the higher your requests-per-minute limits.
Common Errors When Adding a Card
"Your card does not support this type of purchase" — the card is classified as prepaid. You need a card with a debit BIN.
"We are unable to verify your payment method" — IP and card country mismatch. Enable a VPN.
"Card declined" — Russian or other blocked card. Replace with a card carrying a foreign BIN.
FAQ
Can I use the same card for both ChatGPT Plus and the OpenAI API? Yes. One payment method can be linked to both ChatGPT Plus (personal.openai.com) and the API account (platform.openai.com) — they're separate portals.
What happens when the API balance runs out? API calls will fail with an "insufficient_quota" error. Auto-recharge prevents downtime.
Is phone verification required for OpenAI API? Yes. OpenAI requires SMS verification during registration. You can use a foreign number or a virtual SIM service to receive the code.
Get a virtual card for OpenAI API on Marix — works for API billing and ChatGPT Plus.