GPT-5 vs Grok 4
Complete pricing and performance comparison between OpenAI's GPT-5 and xAI's Grok 4.
Quick Verdict
Cheaper
GPT-5
2.4x cheaper input, 1.5x cheaper output
Larger Context
Grok 4
2.0M vs 400K
Higher Quality
GPT-5
Score: 45 vs 42
Faster
GPT-5
60 vs 49 tok/s
Pricing Comparison
| Spec | GPT-5 | Grok 4 | Difference |
|---|---|---|---|
| Provider | OpenAI | xAI | |
| Input / 1M tokens | $1.25 | $3 | GPT-5 is 58% more expensive |
| Output / 1M tokens | $10 | $15 | GPT-5 is 33% more expensive |
| Context Window | 400K | 2.0M | 5x difference |
| Max Output | 16K | 16K | |
| Tokenizer | o200k_base | cl100k_base |
Performance Benchmarks
| Metric | GPT-5 | Grok 4 | Winner |
|---|---|---|---|
| Quality Index | 45 | 42 | GPT-5 |
| Output Speed | 60 tok/s | 49 tok/s | GPT-5 |
| Time to First Token | 117.69s | 9.39s | Grok 4 |
| Value (Quality/$) | 35.7 | 13.8 | 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 | GPT-5 | Grok 4 | Savings |
|---|---|---|---|
Single request 1K in / 300 out | $0.0042 | $0.0075 | GPT-5 saves $0.0033 |
10 requests 10K in / 3K out | $0.042 | $0.075 | GPT-5 saves $0.033 |
100 requests 100K in / 30K out | $0.425 | $0.750 | GPT-5 saves $0.325 |
1,000 requests 1M in / 300K out | $4.25 | $7.50 | GPT-5 saves $3.25 |
10,000 requests 10M in / 3M out | $42.50 | $75.00 | GPT-5 saves $32.50 |
1M requests/mo 1B in / 300M out | $4250.00 | $7500.00 | GPT-5 saves $3250.00 |
Pros & Cons
GPT-5 Strengths
- +Cheaper input tokens
- +Cheaper output tokens
- +Faster output (60 vs 49 tok/s)
- +Higher quality score (45 vs 42)
Grok 4 Strengths
- +Larger context window (2.0M vs 400K)
- +Lower latency (faster first token)
When to Use Each Model
Choose GPT-5 for
- →Budget-conscious projects where cost is the primary factor
- →Tasks requiring maximum accuracy and reasoning
- →Real-time applications, chat, or autocomplete
Choose Grok 4 for
- →Long documents, large codebases, or multi-turn conversations
Frequently Asked Questions
Which is cheaper, GPT-5 or Grok 4?
For input tokens, GPT-5 is 2.4x cheaper at $1.25/1M tokens. For output tokens, GPT-5 is 1.5x cheaper at $10/1M tokens. At typical usage (1M input + 300K output), GPT-5 costs $4.25 vs Grok 4 at $7.50.
What's the context window difference?
GPT-5 supports 400K context (400,000 tokens), while Grok 4 supports 2.0M (2,000,000 tokens). Grok 4 can handle 5x more context in a single request.
Which model has better benchmarks?
Quality Index: GPT-5 scores 45 vs Grok 4 at 42. Speed: GPT-5 generates 60 tok/s vs Grok 4 at 49 tok/s. Time to first token: GPT-5 at 117.69s vs Grok 4 at 9.39s.
When should I choose GPT-5 over Grok 4?
Choose GPT-5 when you need: Cheaper input tokens, Cheaper output tokens, Faster output (60 vs 49 tok/s), Higher quality score (45 vs 42). Choose Grok 4 when you need: Larger context window (2.0M vs 400K), Lower latency (faster first token).
How much would 10,000 API requests cost?
At 1K input + 300 output tokens per request (typical chat): GPT-5 = $42.50, Grok 4 = $75.00. At 10K input + 1K output per request (longer conversations): GPT-5 = $225.00, Grok 4 = $450.00.