Model comparison
Grok 4 Fast vs DeepSeek-R1-0528
- Input
- $0.20 / 1M tokens
- Output
- $0.50 / 1M tokens
- Context
- 2M
- Released
- 2025-09
- Input
- $0.50 / 1M tokens
- Output
- $2.15 / 1M tokens
- Context
- 164K
- Released
- 2025-05-28
Grok 4 Fast scores higher on 5 of the 5 benchmarks both models report; Grok 4 Fast is cheaper on input tokens ($0.2 vs $0.5 per 1M, 2.5×); Grok 4 Fast has the larger context window (2M vs 164K); DeepSeek-R1-0528 ships open weights while Grok 4 Fast is API-only.
Specs and pricing side by side
| Spec | Grok 4 Fast | DeepSeek-R1-0528 |
|---|---|---|
| Maker | xAI (Grok) | DeepSeek |
| Released | 2025-09 | 2025-05-28 |
| Context window | 2M | 164K |
| Max output | not published | 32K tokens (64K max generation length) |
| Input price | $0.20 / 1M tokens | $0.50 / 1M tokens |
| Output price | $0.50 / 1M tokens | $2.15 / 1M tokens |
| Parameters | Undisclosed | 671B total / 37B active (685B on Hugging Face incl. MTP module) |
| License | Proprietary | MIT |
| Weights | API only | Open weights |
| Modalities | Text, Vision | Text |
| Knowledge cutoff | Not publicly disclosed | Not officially disclosed |
Benchmarks both models report
| Benchmark | Grok 4 Fast | DeepSeek-R1-0528 |
|---|---|---|
| GPQA Diamond | 85.7% | 81% |
| AIME 2025 | 92% | 87.5% |
| HMMT 2025 | 93.3% | 79.4% |
| LiveCodeBench | 80% | 73.3% |
| Humanity's Last Exam | 20% | 17.7% |
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 Fast if…
- You care about GPQA Diamond, AIME 2025, HMMT 2025 (it scores higher on 5 shared benchmarks).
- Cost matters: input tokens cost 2.5× less ($0.2 vs $0.5 per 1M).
- You need the longer context (2M vs 164K).
- You need Vision input, which DeepSeek-R1-0528 lacks.
- Your use case is: high-volume production tasks where cost per answer is the deciding factor.
Pick DeepSeek-R1-0528 if…
- You want to self-host or fine-tune (open weights, MIT).
- Your use case is: competition-style math and multi-step logical reasoning.
FAQ
Which is better, Grok 4 Fast or DeepSeek-R1-0528?
Grok 4 Fast scores higher on 5 of the 5 benchmarks both models report; Grok 4 Fast is cheaper on input tokens ($0.2 vs $0.5 per 1M, 2.5×); Grok 4 Fast has the larger context window (2M vs 164K); DeepSeek-R1-0528 ships open weights while Grok 4 Fast is API-only. 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 Fast?
Grok 4 Fast: $0.20 / 1M tokens input, $0.50 / 1M tokens output. DeepSeek-R1-0528: $0.50 / 1M tokens input, $2.15 / 1M tokens output (list API prices as published by each maker).
What are the context windows of Grok 4 Fast and DeepSeek-R1-0528?
Grok 4 Fast offers 2M; DeepSeek-R1-0528 offers 164K with up to 32K tokens (64K max generation length) output.
Is Grok 4 Fast newer than DeepSeek-R1-0528?
Grok 4 Fast was released 2025-09; DeepSeek-R1-0528 was released 2025-05-28.
Go deeper
- Grok 4 Fast: full specs, pricing and benchmarks
- DeepSeek-R1-0528: full specs, pricing and benchmarks
- deepseek r1 0528 vs deepseek r1
- minimax m1 vs deepseek r1 0528
- deepseek v3 2 speciale vs grok 4 fast
- grok 4 1 fast vs grok 4 fast
- deepseek v3 2 exp vs grok 4 fast
- grok 4 vs deepseek r1 0528
- All model comparisons