KCAI

K3 256k API

K3 256k on AtmoRouter — from $0.7425 per million input tokens, from $3.7125 per million output tokens on a 262K context, through one OpenAI-compatible key.

Input · per Mtok

From $0.7425

$3.00 official

Output · per Mtok

From $3.7125

$15.00 official

Off official

75.3%

Context

262K

up to 131K output

3 price tiers

Final prices in USD per million tokens. Each tier is compared with official input and output prices.

InputOutputOffers
$0.742575.2% off official$3.712575.2% off official1
$1.5648% off official$7.848% off official1
$3.742524.7% above official$18.712524.7% above official1

Offer counts are a snapshot and do not guarantee available capacity.

Updated

Prices vary by available offers. Requests can use any listed tier by default. Set maximum input and output prices in Budgets to limit routing.

Model id

kcai/k3-256k

Use this exact id in API calls.

Modality

text,image

Prompt caching supported — cached input $0.07425/Mtok.

Protocols

OpenAI Chat Completions

Anthropic Messages endpoint also available for every model.

Call K3 256k

curl

curl https://atmorouter.dev/v1/chat/completions \
  -H "Authorization: Bearer ar-xxxxxxxxxxxx" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "kcai/k3-256k",
    "messages": [{"role": "user", "content": "Say hello in one word."}]
  }'

Python (OpenAI SDK)

from openai import OpenAI

client = OpenAI(
    base_url="https://atmorouter.dev/v1",
    api_key="ar-xxxxxxxxxxxx",
)

resp = client.chat.completions.create(
    model="kcai/k3-256k",
    messages=[{"role": "user", "content": "Say hello in one word."}],
)
print(resp.choices[0].message.content)

Works with anything OpenAI-compatible — Cursor, Cline, LangChain and more. See the cookbook configs at github.com/Micolaabdi/atmorouter-cookbook and the docs for the Anthropic Messages endpoint.

Questions about K3 256k

How much does K3 256k cost per million tokens?

AtmoRouter prices start from $0.7425 per million input tokens and from $3.7125 per million output tokens. The provider's official list rate is $3.00 / $15.00 — AtmoRouter is 75.3% below it.

Does K3 256k support streaming?

Yes — server-sent events on the OpenAI-compatible endpoint, and the Anthropic Messages endpoint streams natively.

Is there a subscription or minimum spend?

No subscription or minimum commitment. Billing uses the selected offer’s rates, and a minimum request charge applies. See Budgets for the current minimum.

Build with AtmoRouter.