// xAI
Grok 4.20 (reasoning)
A xAI model. 2 prices across 1 channels side by side, each with its source and check date – plus specs, licence, speed and benchmarks.
- Official in/out per 1M
- $1.25 / $2.5
- Lowest (official)
- $1.25 / $2.5
- Context
- 1M
- AA index
- 14.6
Prices checked 2026-10-10Official sources linked on every rowNo estimatesCheapest LLM APIs →
01Specs at a glance
Official values first; gaps filled from OpenRouter’s API where the vendor page is silent.
| Vendor | xAI |
|---|---|
| Context window | 1M (1,000,000 tokens) |
| Max output | 1.8M |
| Input | Text · Image · File/PDF |
| Output | Text |
| Tool calling / JSON | Yes / Yes |
| Weights & licence | Closed · Proprietary (API only) |
| Released | Mar 31, 2026 (OpenRouter listing date) |
| Model IDs | grok-4.20-0309-reasoning · grok-4.20-0309-non-reasoning |
02Prices on 1 channels
Per 1M tokens, in the currency each source publishes (1 USD = 6.7 CNY for the blended column). Sorted: official first, then cheapest.
| Channel | Source | Input | Output | Cache hit | Blended $ | Context | Notes |
|---|---|---|---|---|---|---|---|
| Official Vendor API, billed in USD | Official 10-10 | $1.25 | $2.5 | $0.2 | 1.56 | 1M | Batch −20%Priority 2x; US regional endpoint 1.1x; batch -20% only for grok-4.3 and grok-4.20 family |
| Official Vendor API, billed in USD | Official 10-10 | $1.25 | $2.5 | $0.2 | 1.56 | 1M | Batch −20%Priority 2x; US regional endpoint 1.1x; batch -20% only for grok-4.3 and grok-4.20 family |
“Official” = vendor pricing page; “Platform” = the platform’s own pricing page; “OpenRouter” = price listed on OpenRouter, not checked on the platform’s site. Click a source tag to open the original page.
03Where you can use it
Derived only from the price sources above. Country restrictions are set by each vendor – check their terms before you sign up.
- Vendor API, billed in USD
Official
04Performance
Speed and AA index from Artificial Analysis public leaderboards (not our own tests); benchmark scores from our benchmark library, best result per benchmark.
- AA indexGrok 4.20 0309 (Non-reasoning)
- 14.6
- AA index per $ (blended)
- 9.35
| Benchmark | Best score | Source | Date |
|---|---|---|---|
| GPQA Diamond | 89.3% | independent | 2026-07-13 |
| AIME (OTIS Mock AIME 2024–2025) | 92.2% | independent | 2026-07-13 |
| Terminal-Bench 2.0 | 57.3% | official | 2026-03-10 |
05Price changes we recorded
All price changes →From our daily re-checks of the sources above.
No price change recorded since we started tracking (2026-10-10).
06More from xAI
FAQ
How much does the Grok 4.20 (reasoning) API cost?
On the official pricing page: $1.25 / $2.5 per 1M input / output tokens, cached input $0.2 (checked 2026-10-10).
What is the context window of Grok 4.20 (reasoning)?
1M tokens of context, up to 1.8M output tokens. Platforms may cap it lower – see the table.
Is Grok 4.20 (reasoning) open source?
No. It is only available through APIs and the vendor’s apps.