Model comparison
Grok 4.20 vs Grok 4
- Input
- $1.25 / 1M tokens
- Output
- $2.50 / 1M tokens
- Context
- 1M
- Released
- 2026-03
- Input
- $3.00 / 1M tokens
- Output
- $15.00 / 1M tokens
- Context
- 256K
- Released
- 2025-07-09
Grok 4 scores higher on 1 of the 1 benchmarks both models report; Grok 4.20 is cheaper on input tokens ($1.3 vs $3 per 1M, 2.4×); Grok 4.20 has the larger context window (1M vs 256K).
Specs and pricing side by side
| Spec | Grok 4.20 | Grok 4 |
|---|---|---|
| Maker | xAI (Grok) | xAI (Grok)same |
| Released | 2026-03 | 2025-07-09 |
| Context window | 1M | 256K |
| Max output | not published | 8K |
| Input price | $1.25 / 1M tokens | $3.00 / 1M tokens |
| Output price | $2.50 / 1M tokens | $15.00 / 1M tokens |
| License | Proprietary | Proprietarysame |
| Weights | API only | API onlysame |
| Modalities | Text, Vision | Text, Visionsame |
| Knowledge cutoff | November 2024 | November 2024same |
Not published by either maker: parameters.
Benchmarks both models report
| Benchmark | Grok 4.20 | Grok 4 |
|---|---|---|
| Humanity's Last Exam | 30% | 41% |
Scores are as published by each maker or its cited source; harness, reasoning effort and date can differ between rows, so treat small gaps as ties. Sources are listed on each model page.
Which one should you pick?
Pick Grok 4.20 if…
- Cost matters: input tokens cost 2.4× less ($1.3 vs $3 per 1M).
- You need the longer context (1M vs 256K).
- Your use case is: complex math, science, and multi-step analytical problems that benefit from the reasoning variant.
Pick Grok 4 if…
- You care about Humanity's Last Exam (it scores higher on 1 shared benchmark).
- Your use case is: hard STEM and competition-math problem solving (AIME/HMMT/USAMO-style reasoning).
FAQ
Which is better, Grok 4.20 or Grok 4?
Grok 4 scores higher on 1 of the 1 benchmarks both models report; Grok 4.20 is cheaper on input tokens ($1.3 vs $3 per 1M, 2.4×); Grok 4.20 has the larger context window (1M vs 256K). The better pick depends on whether you value benchmark scores, price per token, context length or openness for your workload.
How much cheaper is Grok 4.20?
Grok 4.20: $1.25 / 1M tokens input, $2.50 / 1M tokens output. Grok 4: $3.00 / 1M tokens input, $15.00 / 1M tokens output (list API prices as published by each maker).
What are the context windows of Grok 4.20 and Grok 4?
Grok 4.20 offers 1M; Grok 4 offers 256K with up to 8K output.
Is Grok 4.20 newer than Grok 4?
Grok 4.20 was released 2026-03; Grok 4 was released 2025-07-09.