xAI: Grok 4.20 API Pricing
xAI: Grok 4.20 costs $1.25 per 1M input tokens and $2.50 per 1M output tokens (cache reads: $0.200). Context window: 2M. Prices verified 2026-10-21 · source
Alternatives to consider
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Cheapest x-ai model — 20% less per month
Rebuilt daily from our snapshot archive — the chart appears once a model has 5+ snapshots of history.
From our own daily snapshot archive — independent of provider announcements.
Intelligence measures reasoning/knowledge/coding benchmarks. A high score with a low blended price = value pick; check the value chart to see where this model lands.
Token economics
| Token type | Price | vs base input |
|---|---|---|
| Standard input | $1.25 | — |
| Cache read | $0.200 | −84% |
| Output | $2.50 | — |
| Web search tool | $5/1k searches | — |
Prompt caching stores repeated context server-side: reads cost far less, but writes carry a one-time premium.
Higher effort = deeper thinking = more reasoning tokens billed as output.
Training data ends here — newer events require retrieval or web search.
What would xAI: Grok 4.20 cost you per month?
| Workload | Requests/mo | Avg tokens (in/out) | Est. monthly cost |
|---|---|---|---|
| Light chatbot | 10,000 | 800 / 400 | $20.00 |
| Coding agent | 5,000 | 8,000 / 2,000 | $75.00 |
| RAG pipeline | 30,000 | 4,000 / 500 | $187.50 |
| Doc summarizer | 2,000 | 20,000 / 1,000 | $55.00 |
Estimates use list prices without prompt caching. Caching can cut input cost by up to 90% on repeated context.
About xAI: Grok 4.20
Grok 4.20 is a reasoning model from xAI with industry-leading speed and agentic tool calling capabilities. It combines the lowest hallucination rate on the market with strict prompt adherance, delivering...
Compare xAI: Grok 4.20 with
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Popular head-to-heads — see all on the comparisons index.
Frequently asked questions
How much does xAI: Grok 4.20 cost?
xAI: Grok 4.20 costs $1.25 per 1M input tokens and $2.50 per 1M output tokens; cached input tokens cost $0.200 per 1M. Verified 2026-10-21 — provider source.
What is the context window?
2M tokens, with up to 1.8M output tokens per response. That's roughly 2500 pages of text in a single request.
Does it support prompt caching?
Yes — cached input is $0.200/1M, about 84% cheaper than standard input. Agents and RAG workloads with repeated context benefit most.
What's a cheaper alternative?
ScaleDown: Summarize saves about 98% on a typical workload with comparable quality.
Official resources
- xAI: Grok 4.20 on OpenRouter — live endpoint, pricing source of record.
- Artificial Analysis leaderboard → — independent intelligence and performance rankings.
- xAI docs → — first-party model specifications and limits.
- Shred your current bill — paste a CSV and see if switching saves money.