Read cost_in_usd_ticks on Grok API responses

Pull the exact billed amount for each request from usage.cost_in_usd_ticks so you can meter a feature, alert on spikes, or sum a session without waiting on a Console invoice. Official Cost Tracking documents the field on Chat Completions, the Responses API, image generation, and video generation. The value is already after prompt-cache discounts and includes server-side tool invocations for that single call. Create a key and load credits at console.x.ai.

What you need

An XAI_API_KEY, a client that reads the usage object (curl, OpenAI-compatible SDK, or xAI SDK), and a place to store per-request dollars. Neighboring jobs include Get batch cost breakdown when the work is queued, Explore API usage in the xAI Console for team-level charts, and Get usage analytics via the Management API for programmatic rollups. More API jobs live on the API hub.

Convert ticks to dollars

1. Export the key outside of source control, then run a Responses call and print the ticks field:

export XAI_API_KEY="your_api_key"

curl https://api.x.ai/v1/responses \
  -H "Authorization: Bearer $XAI_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "grok-4.7",
    "input": "Say hello"
  }' | jq '.usage.cost_in_usd_ticks'

2. Divide by 10_000_000_000 (10^10). Official docs use that scale so totals stay exact when you sum thousands of requests — for example 37756000 ticks is about $0.0038.

3. Or use the xAI Python SDK, which exposes both raw ticks and a cost_usd helper:

import os
from xai_sdk import Client
from xai_sdk.chat import user

client = Client(api_key=os.getenv("XAI_API_KEY"))
chat = client.chat.create(model="grok-4.7", messages=[user("Say hello")])
response = chat.sample()

print(f"Cost: ${response.cost_usd:.6f}")
print(f"Cost (ticks): {response.usage.cost_in_usd_ticks}")

Streaming and agentic loops

On the OpenAI-compatible SDK, set stream_options: { "include_usage": true } so the final empty-choices chunk carries usage (and therefore cost_in_usd_ticks). Intermediate chunks omit usage. With the xAI SDK stream helper, read response.cost_usd after the loop finishes. When the request uses server-side tools such as web search or code execution, the returned ticks already cover every decode and tool call in that agentic loop — you do not add them up yourself for a single request.

Sum a multi-turn session

cost_in_usd_ticks is per request, not cumulative. Keep a running total in your app after each turn (add response.cost_usd or ticks / 1e10). Image and video responses expose the same field on their usage object; Batch jobs expose per-request costs plus a batch-level cost_breakdown covered in the sibling Batch cost post.

Pitfalls

Treating ticks as cents or as raw dollars understates or overstates spend by orders of magnitude — always divide by 1e10. Expecting a streaming OpenAI client to show cost without include_usage leaves you with no usage object until you enable it. Assuming the Vercel AI SDK surfaces cost_in_usd_ticks today is wrong — the Cost Tracking page says to use the OpenAI SDK or REST for that field. Mixing Console prepaid balance charts with per-request ticks without converting units will not reconcile cleanly.