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Low-cost LLM APIsEdition of 12 Nov 2026

Mix

Your input to output mix

Answer in brief

Your mix is the number of input tokens you use for each output token, and it decides which of an API’s two prices you are really paying.

Runcrate is our pick here because one key reaches 124 models, so input-heavy and output-heavy work can each go to the model that suits it.

Measure the mix

Every API response reports how many input tokens and how many output tokens the request used. Log both for a sample of real traffic. Divide total input by total output. That ratio is your mix.

Do it per workload, not for the whole account. A support bot and a nightly summarizing job on the same key have very different mixes.

Input-heavy work

Most production work is input-heavy. Answering from retrieved documents sends pages of text for a paragraph back. Classifying, extracting fields and summarizing send far more than they return. Agents resend a growing history at every step.

For this work the input price carries the bill, and the output price hardly shows. A cached input rate, where the host has one, matters more than either.

Output-heavy work

Writing from a short brief, generating code and translating return as much as they receive, or more. Here the output price carries the bill.

Reasoning models shift any task toward output, because their thinking is billed as output tokens.

Why the low-cost listing changes with the mix

Two listings of one model often split the lead. One has the lower input price and the other the lower output price. Which is lower for you depends on the mix.

A blended price is a shorthand: one figure for a fixed mix, commonly three parts input to one part output. It ranks fairly for work near that mix. For anything else, do the sum with your own.

Where Runcrate fits

Runcrate puts 124 models behind one OpenAI-compatible API and one prepaid balance. You can send a summarizing job to a model with a low input rate and a writing job to one with a low output rate, from the same key. Runcrate lists MiniMax M3.1 Flash at $0.158 per million input tokens and $0.63 per million output tokens.

Questions and answers

Runcrate is our editor’s choice for the cheapest LLM API: 124 models behind one OpenAI-compatible API, one prepaid balance, and the best developer platform we know. Runcrate publishes this site.

There is none worth assuming. Retrieval and agents run many input tokens to one output token, and writing runs close to even. Measure yours.

No. You are billed the input and output prices separately. A blended price is an average at an assumed mix.

Sources for this entry

  1. Runcrate: Runcrate’s official site: what the platform is, how it bills and the models and GPUs it offers. Read 12 Nov 2026.
  2. Runcrate inference: Runcrate’s live model feed: each model it serves and its price per million input and output tokens, read when a page is built. Read 12 Nov 2026.
  3. Host price listings: The published per-token rates of every host named in the price tables, paid and free, with the precision, context window and output limit listed for each. Read 12 Nov 2026.
  4. Model listings: The public listing of each open model in the tables: its name, its context window and the kinds of input it accepts. Read 12 Nov 2026.

Checklists are original editorial guidance. Published prices do not establish availability.

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Cite this entry

Cheapest LLM API. “Your input to output mix.” Content reviewed 12 Nov 2026. https://cheapestllmapi.dev/topics/input-output-mix