Output Length Cost Impact
Shows what shortening the answer is worth per month, and what 100 extra output tokens on every request cost you.
Output is 70.0% of this workload's bill today, and every 100 output tokens you add to every request costs $300.00 a month.
- Input cost per request
- $0.0045
- Output cost per request now
- $0.01
- Output cost per request at target
- $0.0037
- Total per request now → target
- $0.01 → $0.0083
- Output share of the bill now
- 70.0%
- Output tokens removed per request
- 450
- Monthly bill now → target
- $3,000 → $1,650
- Annual saving
- $16,200
- Cost of +100 output tokens on every request
- $300.00 / month
- One output token costs as much as
- 5.0 input tokens
The lever nobody pulls
Output is the expensive half of an inference bill and the half almost nobody tunes. There are two reasons for that. The obvious one is price: output tokens are usually billed at a multiple of input tokens, because generating them is sequential work on a GPU while reading the prompt is parallel. The second is that output length is the term you control most directly — you can ask for less, cap it, or change the format — and precisely because it is easy, it gets left at whatever the model happened to produce.
The useful line in the breakdown is the last but one: what 100 extra output tokens on every request cost per month. That converts a wording decision into money. "Explain your reasoning" is not a free instruction; neither is a response schema with verbose field names, or a system prompt that invites a preamble. On a workload at any scale, a habit of two polite sentences before the answer is a line item.
What this does not capture: shortening an answer can cost you accuracy on tasks where the model genuinely benefits from working through the problem, and a truncated answer that has to be regenerated costs twice. A hard max-tokens cap is not a saving if it produces cut-off JSON that fails validation and gets retried — the retry pays for both. Shorten by asking for less, not only by capping; use the cap as a guard against the tail, and check what share of requests hit it.