How to estimate monthly token usage
Last updated 2026-07-18

You do not need perfect telemetry to create a useful AI budget. You need a reasonable model of monthly volume. The best starting point is simple: count how often the workflow runs, estimate how much text goes into the model, and estimate how much text comes back. Keep input and output separate, because providers often price them differently.
Start with the business event
Use the real event that triggers the model call. A support bot may run per conversation or per message. A code review assistant may run per pull request. A document workflow may run per uploaded file. A meeting assistant may run per transcript. Once you can count the event, monthly cost becomes easier to forecast.
Estimate input honestly
Input includes more than the user prompt. Count the system prompt, examples, retrieved documents, tool results, conversation history, schemas, and file excerpts. Many teams underestimate this because the visible user message is short while the hidden context is large. If a workflow uses retrieval, estimate how many chunks are usually inserted.
For rough planning, create three scenarios: low, expected, and high. The high case matters because successful AI features often grow in usage. A pilot with 1,000 monthly requests can become 100,000 quickly if the workflow actually helps people.
Estimate output separately
Output is where many estimates break. A classifier may return 50 tokens. A report writer may return 3,000. A coding assistant may produce code, comments, tests, and explanation. Since output is often more expensive, a small change in answer length can shift monthly cost and provider ranking.
Convert to monthly totals
Multiply events by average input and output. For example: 20,000 support conversations per month, 1,500 input tokens each, and 250 output tokens each equals 30 million input tokens and 5 million output tokens. Put those numbers into the comparison tool rather than trying to eyeball unit prices.
References and fact checks
- Anthropic Claude API pricing - shows separate input, output, cache write, and cache hit units
- Google Gemini API pricing - documents input/output tokens plus media and batch-related billing concepts
- AWS Bedrock cost report documentation - useful for reconciling estimated token usage with billing data
How to do this in AICC
Turn the article into an answer you can use
Use AICC to turn rough workload assumptions into monthly input and output volumes, then check how those volumes affect provider cost.
- 1
Write down the triggering event
Before opening the tools, define the event: support conversation, document, pull request, meeting transcript, generated report, or chat turn. This is the unit you will multiply by monthly volume.
- 2
Estimate input and output separately
Use the article method to estimate average input tokens and output tokens per event. Keep prompt, retrieved context, chat history, and generated answer length separate.
- 3
Enter the monthly totals in Compare
Open the Comparison tool and enter total monthly input and output volumes. If the workflow also uses images, video, audio, seats, or volume assumptions, fill those fields too.
- 4
Stress-test the high case
Increase the monthly volume or output length to see where cost changes materially. This teaches you which assumption matters most before the invoice arrives.
What you should have at the end
You should have low, expected, and high monthly usage cases and a provider comparison that reflects your actual workload shape.
Frequently asked questions
What's the biggest mistake teams make when estimating input tokens?
Undercounting hidden context — the visible user message is often short, but system prompts, retrieved documents, tool results, and chat history can make real input volume much larger.
Why build low, expected, and high usage scenarios instead of one estimate?
Successful AI features tend to grow quickly in usage — a pilot with 1,000 monthly requests can become 100,000 once it proves useful, and the high case protects your budget plan.
Should I estimate input and output tokens together or separately?
Separately. Providers typically price them differently, and since output is often the pricier side, small changes in answer length can shift which provider is cheapest.