Grok 4-20 vs o3
Complete pricing and performance comparison between xAI's Grok 4-20 and OpenAI's o3.
Quick Verdict
Cheaper
Grok 4-20
1.0x cheaper input, 1.3x cheaper output
Larger Context
o3
200K vs 131K
Higher Quality
Grok 4-20
Score: 49 vs 38
Faster
Grok 4-20
101 vs 74 tok/s
Pricing Comparison
| Spec | Grok 4-20 | o3 | Difference |
|---|---|---|---|
| Provider | xAI | OpenAI | |
| Input / 1M tokens | $2 | $2 | Same |
| Output / 1M tokens | $6 | $8 | Grok 4-20 is 25% more expensive |
| Context Window | 131K | 200K | 2x difference |
| Max Output | 16K | 100K | |
| Tokenizer | cl100k_base | o200k_base |
Performance Benchmarks
| Metric | Grok 4-20 | o3 | Winner |
|---|---|---|---|
| Quality Index | 49 | 38 | Grok 4-20 |
| Output Speed | 101 tok/s | 74 tok/s | Grok 4-20 |
| Time to First Token | 20.69s | 7.97s | o3 |
| Value (Quality/$) | 24.3 | 19.2 | Higher = better value |
Benchmark data from Artificial Analysis. Quality Index is a composite score across reasoning, coding, and knowledge tasks.
Cost at Scale
Estimated cost at different usage levels (3:1 input-to-output token ratio, typical for chat).
| Usage | Grok 4-20 | o3 | Savings |
|---|---|---|---|
Single request 1K in / 300 out | $0.0038 | $0.0044 | Same |
10 requests 10K in / 3K out | $0.038 | $0.044 | Grok 4-20 saves $0.0060 |
100 requests 100K in / 30K out | $0.380 | $0.440 | Grok 4-20 saves $0.060 |
1,000 requests 1M in / 300K out | $3.80 | $4.40 | Grok 4-20 saves $0.600 |
10,000 requests 10M in / 3M out | $38.00 | $44.00 | Grok 4-20 saves $6.00 |
1M requests/mo 1B in / 300M out | $3800.00 | $4400.00 | Grok 4-20 saves $600.00 |
Pros & Cons
Grok 4-20 Strengths
- +Cheaper output tokens
- +Faster output (101 vs 74 tok/s)
- +Higher quality score (49 vs 38)
o3 Strengths
- +Larger context window (200K vs 131K)
- +Higher max output tokens
- +Lower latency (faster first token)
When to Use Each Model
Choose Grok 4-20 for
- →Tasks requiring maximum accuracy and reasoning
- →Real-time applications, chat, or autocomplete
Choose o3 for
- →Long documents, large codebases, or multi-turn conversations
- →Generating long-form content or detailed code
Frequently Asked Questions
Which is cheaper, Grok 4-20 or o3?
For input tokens, Grok 4-20 is 1.0x cheaper at $2/1M tokens. For output tokens, Grok 4-20 is 1.3x cheaper at $6/1M tokens. At typical usage (1M input + 300K output), Grok 4-20 costs $3.80 vs o3 at $4.40.
What's the context window difference?
Grok 4-20 supports 131K context (131,072 tokens), while o3 supports 200K (200,000 tokens). o3 can handle 2x more context in a single request.
Which model has better benchmarks?
Quality Index: Grok 4-20 scores 49 vs o3 at 38. Speed: Grok 4-20 generates 101 tok/s vs o3 at 74 tok/s. Time to first token: Grok 4-20 at 20.69s vs o3 at 7.97s.
When should I choose Grok 4-20 over o3?
Choose Grok 4-20 when you need: Cheaper output tokens, Faster output (101 vs 74 tok/s), Higher quality score (49 vs 38). Choose o3 when you need: Larger context window (200K vs 131K), Higher max output tokens, Lower latency (faster first token).
How much would 10,000 API requests cost?
At 1K input + 300 output tokens per request (typical chat): Grok 4-20 = $38.00, o3 = $44.00. At 10K input + 1K output per request (longer conversations): Grok 4-20 = $260.00, o3 = $280.00.