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Concept card · Ship & Maintain

Cost forecasting

Cost forecasting is multiplying token counts by the provider's published rates, then by how often the workflow runs.

Estimating spend from token volume, rates, and how often a workflow runs.

Last checked 2026-10-18 Free card 5 min

Ask about Cost forecasting

What changed

Oct 18: First card. The picture multiplies one assumed request by a vendor-reported gpt-4.1 rate. Sources are the OpenAI and Anthropic pricing pages.

1 What it is

Providers publish a price per token, and input and output are different rates. OpenAI's pricing page lists standard prices per 1,000,000 tokens, with separate columns for input, cached input, and output, and a higher long-context rate on some models. Anthropic's pricing page lists base input tokens and output tokens in USD per million tokens, plus separate cache-write and cache-hit rates. A forecast is those rates times the tokens one run uses, times how many runs you expect. The run count is an assumption until you have measured traffic. Cached input is a different rate from uncached input. This card does not invent a market price.

Illustration. Token counts and the run count are assumptions for this picture, not measured usage. Rates are vendor-reported from OpenAI's API pricing page for gpt-4.1, standard short-context columns, checked 2026-10-18: input $2.00 and output $8.00 per 1,000,000 tokens. Cached input on that row is $0.50 and is not used here. Other models, and Anthropic's table, use different rates. Prices may change.

Assumed request: 2,000 uncached input tokens and 500 output tokens.

Uncached input2,000 × $2.00 ÷ 1,000,000 = $0.004

Output500 × $8.00 ÷ 1,000,000 = $0.004

This run$0.004 + $0.004 = $0.008

The $0.008 figure is this picture's arithmetic on the assumed tokens and the vendor-reported gpt-4.1 rates. It is not a bill.

2 Why it matters

Cost

The forecast is only as current as the pricing page. Copy the input, cached-input, and output rates for the model you will ship, and write the date next to them. OpenAI's page prices cached input separately from uncached input. Anthropic's page does the same with cache hits.

Quality

A forecast that prices output tokens at the input rate will be low on the rows checked for this card. On OpenAI's gpt-4.1 standard short-context row, output is $8.00 per 1,000,000 tokens and input is $2.00. Those amounts are vendor-reported.

Risk

A monthly number with no alert is a guess you will not notice until the invoice. Pick the number that should slow or stop the feature, and open the pricing page again on launch day.

3 How to apply · try today

On one real request, write uncached input tokens, cached input tokens, and output tokens as three numbers. Open the provider's current pricing page, copy the matching rates, and multiply. Then multiply by a monthly run count you label as an assumption.

Common mistake

Using one remembered price per request. Input, cached input, and output are different rates, and a longer prompt can cross into a higher column on the same pricing page.

Self-check

What do you multiply to forecast spend?

Questions

What is cost forecasting?
Cost forecasting is multiplying token counts by the provider's published rates, then by how often the workflow runs.
Is the $8.00 in the picture a real monthly bill?
No. It is 1,000 times this picture's $0.008 run. The 1,000 runs and the token counts are assumptions. The gpt-4.1 rates are vendor-reported from OpenAI's pricing page on 2026-10-18 and may change.
Can one rate cover input and output?
OpenAI's and Anthropic's pricing pages list input and output separately. Use the column that matches the tokens you counted.