How to Track Your OpenAI API Spending

1. Check Your Total Spending

The easiest way is through the OpenAI Dashboard:
OpenAI Usage
Here, you can view your monthly spending and set a monthly limit.

2. Calculate the Cost of a Specific Query

The cost of a query depends on the number of tokens and the model used.
Key factors affecting the cost:

• Input length (number of tokens in the prompt)
• Output length (number of tokens in the generated response)
• Model used (e.g., GPT-4-Turbo, GPT-3.5-Turbo)
• Token type (input, cached input, output – each has a different price)

3. Use the tiktoken Library to Count Tokens

OpenAI provides the tiktoken library, which allows you to count the number of tokens in input and output.
Example code for counting tokens: is here

4. Calculate the Cost Based on Current Pricing

OpenAI provides current pricing on the pricing page.
The cost is calculated using the formula:

Cost=(input tokens×input price)+(output tokens×output price)\text{Cost} = (\text{input tokens} \times \text{input price}) + (\text{output tokens} \times \text{output price})Cost=(input tokens×input price)+(output tokens×output price)

For example, if the GPT-4 Turbo model costs $0.01 per 1,000 input tokens and $0.03 per 1,000 output tokens, then:

• Input tokens: 500 → 500/1000×0.01=0.005500 / 1000 \times 0.01 = 0.005500/1000×0.01=0.005 USD
• Output tokens: 1000 → 1000/1000×0.03=0.031000 / 1000 \times 0.03 = 0.031000/1000×0.03=0.03 USD
• Total cost: 0.005 + 0.03 = 0.035 USD

5. Alternative Methods to Calculate Token Usage

If you use the OpenAI API, you can get token usage directly from the API response—OpenAI returns tokenization details in the response is here

Summary

• Check total spending via the OpenAI Dashboard.
• Count tokens using the tiktoken library.
• Calculate the cost by multiplying tokens by the current pricing rate.
• Use API responses to get direct token usage data.

The calculation is straightforward, and OpenAI API is quite affordable—even extensive queries cost just a few cents. 🚀