Verified65% confidenceFactExact time
Cached input tokens are a discount mechanism offered by providers such as OpenAI for large repeated prefixes (such as system prompts, long documents, and few-shot examples); input tokens that hit the cache are billed at a lower rate, usually only about one-tenth of the standard input price.
3
Sources
65%
Confidence
Long-term
Relevance
10/13/2026
First Seen
Sources
Related Entities
Related Claims
VerifiedToken caching (Prompt Caching) is a cost-optimization mechanism in large model APIs; when the same prefix appears repeatedly across multiple requests, the computation result can be cached and charged at a lower rate.79% similarUnverifiedOpenAI reports cached input tokens in usage.prompt_tokens_details.cached_tokens, and the billing rate is lower; ignoring this causes costs to be overestimated.79% similarUnverifiedOpenAI provides a Prompt Caching mechanism for models such as Codex, which allows reuse of previously computed KV cache when the prefix token sequence of a request is identical to a prior one, reducing the billing price for that portion (typically 50% or even lower than the normal price).79% similarVerifiedOpenAI's API billing distinguishes between input tokens and output tokens, with output tokens typically priced higher.78% similarUnverifiedPrompt caching usually has an expiration period, requires rewriting after content changes, and the cache discount applies only to the input side, while output tokens are still billed at the standard rate.77% similar
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