Verdict
computed from the published numbersGPT-5.4 wins on coding, on intelligence and on context window. Mercury 2 wins on price.
Price
Mercury 2
Coding
GPT-5.4
Intelligence
GPT-5.4
Context window
GPT-5.4
Key takeaways
who wins on what, from the published numbersGPT-5.4 wins
- Larger context window (1.1M vs 128K)
- Higher max output (128K vs 50K)
- More serving providers (4 vs 2)
- Supports vision
- Has reasoning mode
- Has web search
Mercury 2 wins
- Cheaper input ($2.50 vs $0.25 /1M)
- Cheaper output ($15.00 vs $0.75 /1M)
Cheaper overall
Mercury 2
$0.25 + $0.75 /1M
Larger context
GPT-5.4
1.1M
More providers
GPT-5.4
4 providers
Pricing & specs
cheapest serving route · per 1M tokens| GPT-5.4 | Mercury 2 | |
|---|---|---|
| Input $/1M | $2.50 | $0.25 best |
| Output $/1M | $15.00 | $0.75 best |
| Context window | 1.1M best | 128K |
| Max output | 128K best | 50K |
| Serving providers | 4 best | 2 |
| Released | 2026-03-05 | 2026-02-24 |
Benchmarks
Artificial Analysis indices, side by side| GPT-5.4 | Mercury 2 | |
|---|---|---|
| Intelligence | 53.1 best | 21.9 |
| Coding | 71.0 best | 31.1 |
| GPQA Diamond | 92% best | 77% |
| Output speed | 135 t/s | 939 t/s best |
| Latency (TTFT) | 143.52s | 3.44s best |
Cost calculator
choose a serving route for each sideInput tokens / month
Output tokens / month
GPT-5.4
via Databricks
$27
Mercury 2
via Inception
$2.00
Capabilities
feature support, side by side| Feature | GPT-5.4 | Mercury 2 |
|---|---|---|
| Vision | ✓ | — |
| Tool use | ✓ | ✓ |
| Reasoning | ✓ | — |
| Audio | — | — |
| Prompt caching | ✓ | ✓ |
| Structured output | ✓ | ✓ |
| Web search | ✓ | — |
Related comparisons
Frequently asked questions
Which is cheaper, GPT-5.4 or Mercury 2?
Mercury 2 is cheaper for input ($2.50 vs $0.25 per 1M tokens). Mercury 2 is cheaper for output ($15.00 vs $0.75 per 1M tokens).
What is the context window difference between GPT-5.4 and Mercury 2?
GPT-5.4 has a 1.1M-token context window and Mercury 2 has 128K tokens, so GPT-5.4 can take a larger prompt.
How do GPT-5.4 and Mercury 2 compare on benchmarks?
On the tracked Artificial Analysis indices, GPT-5.4 leads on coding, and GPT-5.4 leads on intelligence.
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