ChatGPT Cost CalculatorHow Much Does the ChatGPT API Actually Cost?
The ChatGPT API charges per token — small text units that average about 4 characters in English. Every API call has two costs: input tokens (your prompt) and output tokens (the response). Output tokens typically cost 3-5x more than input tokens, which means the length of the AI's response is usually the biggest cost driver.
As of April 2026, GPT-4o costs $2.50 USD per million input tokens and $10.00 per million output tokens. For a typical business sending 500 API calls per day with 1,000 input tokens and 500 output tokens each, that works out to roughly $56 AUD per month. GPT-4o Mini drops that to under $5 AUD per month for the same volume — a 90% saving with only a modest quality trade-off.
But ChatGPT is not the only option. Claude Sonnet 4 from Anthropic offers competitive pricing at $3.00/$15.00 per million tokens with a 200K context window. Google's Gemini 2.0 Flash is the budget leader at just $0.10/$0.40 per million tokens, making it ideal for high-volume applications where cost matters more than maximum quality. Meta's open-source Llama models, available through hosted providers, offer another cost-effective alternative.
The right model depends on your use case. Customer support chatbots handling thousands of short conversations benefit from cheap, fast models like GPT-4o Mini or Gemini Flash. Complex reasoning tasks — legal analysis, code generation, research — justify the higher cost of Claude Opus 4 or GPT-4 Turbo. Our AI Token Counter helps you estimate token counts for your specific prompts, and the LLM Model Price Comparison tool shows pricing across all providers at a glance.
For Australian businesses, remember that all API costs are billed in USD. At the current rate of approximately 1.55 AUD per USD, it pays to compare carefully before committing to a provider. Use this free calculator to model your actual usage and find the cheapest option for your workload.