xAI

Grok 4.5

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xAI's current flagship. 500K context, vision, file input, reasoning; the rate doubles above 200K prompt tokens.

Modalities

Text+Image → Text

Input

$2.70 /1M

Output

$8.10 /1M

Context

500K

Speed

medium

Pricing

Pay per token. Cached input is billed at 10% of the input rate.

$2.70 /1M input$8.10 /1M output

Hobby10 req/day · 2K in / 500 out

~$2.83/mo

Production1,000 req/day · 2K in / 500 out

~$284/mo

Scale20,000 req/day · 2K in / 500 out

~$5,670/mo

+ Estimate your workload

Requests / day1,000

Input tokens / request2,000

Output tokens / request500

Estimated monthly cost

$284

$9.45 / day on Grok 4.5

Same workload on:

Grok 4.20 Multi-Agent$152-46%

Grok 4.20$152-46%

Estimates use list pricing. Actual bills depend on real token counts — every response includes its exact cost.

How it compares

Against the peers people actually weigh it against.

Spec	Grok 4.5	Grok 4.20 Multi-Agent	Grok 4.20
Input /1M	$2.70	$1.688	$1.688
Output /1M	$8.10	$3.375	$3.375
Context	500K	2M	2M
Tools	Yes	No	Yes
Reasoning	Yes	Yes	Yes
Speed	medium	slow	medium

Quick start

Up and running in under two minutes.

1
Create an API key
Sign up and grab a key from the dashboard — $0.50 free credit, no card required.
Get API key →

Make your first request

Drop in your key and send a chat completion — fully OpenAI-compatible.

curl https://kymaapi.com/v1/chat/completions \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "grok-4.5",
    "messages": [
      {"role": "user", "content": "Explain prompt caching in one paragraph."}
    ]
  }'

Stream responses

Add "stream": true to receive tokens as they arrive.

curl https://kymaapi.com/v1/chat/completions \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "grok-4.5",
    "stream": true,
    "messages": [{"role": "user", "content": "Hello!"}]
  }'

FAQ

Common questions about this model.

What is the context window of Grok 4.5?

Grok 4.5 has a 500K-token context window — roughly 735 pages of text in a single request.

How much does the Grok 4.5 API cost?

$2.70 per 1M input tokens and $8.10 per 1M output tokens. No subscription; you pay only for what you use.

Does Grok 4.5 support function calling?

Yes — Grok 4.5 supports tool/function calling and structured outputs (JSON mode), so it works with agent frameworks out of the box.

How do I use Grok 4.5?

Kyma is OpenAI-compatible: point your SDK's base URL at https://kymaapi.com/v1, use your Kyma API key, and set the model to grok-4.5. Signing up is free and includes $0.50 of credit — no card required.

Start with $0.50 free credit — no card required.Create account →

More models by xAI

Model	Context	Input	Output
Grok Build	256K	$1.389	$2.777
Grok 4.3	1M	$1.688	$3.375
Grok 4.20	2M	$1.688	$3.375
Grok 4.20 Multi-Agent	2M	$1.688	$3.375