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Low-cost LLM APIsEdition of 12 Nov 2026
Cheapest LLM APIRuncrate Reference
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Context

Long context on a small budget

Answer in brief

Long prompts are billed as input on every request, so on long-context work the input price and the context window decide what is cheap.

Runcrate is our pick here because its 124 models share one OpenAI-compatible API, so long documents can go to a model with a low input rate while short tasks go elsewhere.

Long context is an input cost

A context window is the most tokens a model takes in one request. Filling it is not free. Every token in the window is billed as input, each time you send it.

A question about a long contract sends the whole contract. Ten questions send it ten times. The answers are short, so nearly all of the bill is input.

Check the window on the low rate

Hosts list the same model with different context windows. In the listings read for this site, Qwen3.8 27B appears with windows from 65,536 tokens up to 1,048,575.

The lowest listed rate can belong to the shortest window. If your prompt does not fit, that rate is not yours. Filter by window first, then compare price.

Cheaper than a long prompt

The lowest-cost long prompt is a shorter one. Split documents into passages, find the few that bear on the question and send only those. This is retrieval, and it turns a very large input into a small one.

Where the whole document must be read, ask every question in one request, or use a cached input rate so the repeat is billed at less.

Comparing input prices

For long-context work, sort by input price. On 12 Nov 2026, the lowest listed input price for Qwen3.8 27B was $0.035 per million tokens. For DeepSeek V4.1 Flash 1017 it was $0.022 per million tokens.

Then multiply by your real prompt length and your requests per day. A small gap per million tokens is a large gap when every request carries a long document.

Where Runcrate fits

Runcrate serves 124 models behind one OpenAI-compatible API. You can route long documents to one model and short tasks to another from one key and one prepaid balance. Runcrate lists Qwen3.8 27B at $0.158 per million input 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.

The window is a limit, not a charge. What costs more is filling it, because every token in it is billed as input on every request.

Nearly always. Sending the few passages that matter costs a fraction of sending the whole document each time.

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. “Long context on a small budget.” Content reviewed 12 Nov 2026. https://cheapestllmapi.dev/topics/long-context-on-a-budget