OpenAI API Error 429: Quota Exceeded

import openai
openai.api_key = "YOUR_API_KEY"  # Replace with your actual key

try:
    response = openai.ChatCompletion.create(
        model="gpt-3.5-turbo",
        messages=[{"role": "user", "content": "Explain quantum computing in simple terms"}]
    )
    print(response.choices[0].message.content)
except openai.error.RateLimitError as e:
    print(f"Error occurred: {e}")

Problem Statement

The OpenAI API error 429 with message "You exceeded your current quota, please check your plan and billing details" occurs when:

1. Your free trial credits have been exhausted (typically $5-18 worth of tokens)
2. Your account hasn't transitioned to a paid plan after the free tier expiration
3. Your usage exceeds defined rate limits (even with an active plan)
4. Your API key was generated pre-paid plan activation

Common triggers include:

• Using high-volume/complex API requests
• Processing large datasets
• Multiple accounts sharing the same phone number
• Old API keys created before billing configuration

Key indicators before this error

• Free tokens expired after 3 months from account creation
• Usage dashboard shows $0 remaining credit
• Multiple accounts created with the same phone number

TIMING CONSIDERATION

After upgrading to a paid plan, allow 10-60 minutes for activation. API calls may still fail during this transition period.

Recommended Solutions

1. Activate OpenAI paid billing

Upgrade to a paid plan and add valid payment method:

# API behaves differently after plan activation
# Free accounts: Error 429 immediately 
# Paid accounts: Error 429 only when exceeding limits

1. Create or log in to your OpenAI Account
2. Navigate: Account → Billing → Payment Methods
3. Add valid credit/debit card
4. Confirm usage limits ($5 monthly minimum)

KEY REGENERATION REQUIRED

API keys generated before account upgrade remain associated with free-tier restrictions. Always create new keys after payment setup.

2. Generate new API keys

1. Visit API key management
2. Click + Create new secret key
3. Replace old key in your application:

# Replace existing key reference
openai.api_key = "new_sk-xxxxxxxxxxxxxxxxxxxxxxxxxxxx"

4. (Optional) Delete old API keys under API keys → Manage

Best Practice: Delete unused keys and set spending limits under Usage limits to avoid unexpected costs.

3. Verify account identity uniqueness

Ensure no multiple accounts share phone numbers:

1. Each phone number qualifies for only one free credit allocation
2. Check Account Settings → Memberships
3. Delete secondary accounts sharing your number
4. Use distinct numbers/accounts for additional free trials

4. Manage organizations and billing

For enterprise/team accounts:

1. Visit Default Organizations
2. Validate active organization association
3. Re-confirm payment methods tied to organizations

Post-Fix Verification

1. Check Usage Dashboard credits
2. Test with a small request:

# Minimal test request
openai.Completion.create(
    engine="text-davinci-003",
    prompt="Test",
    max_tokens=5
)

3. Allow 10 minutes propagation time if still failing after upgrade

For recurring issues:

1. Configure rate limiting (GPt-3.5 default: 3,500 RPM / 90,000 TPM)
2. Implement automatic retries with exponential backoff
3. Monitor usage via X-RateLimit-* response headers

Troubleshooting Supplement

Symptom	Resolution
"You've reached your usage limit"	Wait 15 minutes after account upgrade
Multiple organization keys	Associate key with correct organization
Payment succeeded but key fails	Generate post-payment key and validate
Free trial expired yesterday	Complete payment setup first, then retry

BILLING TIMELINE

Free tier accounts expire automatically 90 days after creation. Paid subscriptions start immediately upon payment method addition - no proration for partial months.

Preventative Measures

• Monitor balance: openai.Usage.retrieve()
• Set hard limits: Billing settings → Usage limits
• Use webhooks for notifications
• Implement user-level rate limiting

# Python usage check example
usage = openai.Usage.retrieve()
print(f"Current usage: ${usage.total_usage/100:.2f}")

For persistent errors, contact OpenAI Support with:

1. API key prefix (e.g., sk-ABC123...)
2. Full error response
3. Account email and organization ID