TokenBingeby JoDevelop
All model prices
xAI

grok-4-20-0309-reasoning

Official price

Model overview

Deliberation before answering is the only thing that sets this build apart, because the meter does not move: $1.25 per million input tokens, $0.20 cached and $2.50 output are identical to its non-reasoning twin, to the multi-agent build and to grok-4-3, all on the same 1,000,000-token window. The cost difference therefore lives entirely in token volume. Reasoning traces are billed at the output rate, twice the input rate, so a short answer can cost several times its visible length once the chain is counted. Pick it when correctness on multi-step problems matters more than a predictable invoice, and measure actual output counts rather than the rate card, which will show four identical rows.

Billing conditions: Standard short-context API price. At 200K input tokens or more, xAI applies its published long-context rates to all tokens in the request.

Context window
1,000,000 tokens
Knowledge cutoff
Price last verified
First observed

Descriptions, capabilities, and tariffs come from the linked source. First-party prices take priority; OpenRouter fallbacks are labelled.

Capabilities and formats

  • text
  • reasoning
  • tools
  • structured output

Performance references

No comparable benchmark data is currently available.

PRICE EVOLUTION

Price history

Original observation and every later change, including any change of price source.

  1. Original observed priceOfficial price
    Input: $1.25Cached input: $0.2Cache write 5m: Cache write 1h: Output: $2.5