Key Takeaways
GPT-5 Codex wins:
- Cheaper input tokens
- Larger context window
- Faster response time
- Higher intelligence benchmark
- Better at coding
- Better at math
- Supports tool calls
Sonar Reasoning Pro wins:
- Cheaper output tokens
- Has reasoning mode
Price Advantage
GPT-5 Codex
Benchmark Advantage
GPT-5 Codex
Context Window
GPT-5 Codex
Speed
GPT-5 Codex
Pricing Comparison
Price Comparison
| Metric | GPT-5 Codex | Sonar Reasoning Pro | Winner |
|---|---|---|---|
| Input (per 1M tokens) | $1.25 | $2.00 | GPT-5 Codex |
| Output (per 1M tokens) | $10.00 | $8.00 | Sonar Reasoning Pro |
| Cache Read (per 1M) | $125000.00 | N/A | GPT-5 Codex |
Using a 3:1 input/output ratio, GPT-5 Codex is 2% cheaper overall.
GPT-5 Codex Providers
OpenAI $1.25 (Cheapest)
Sonar Reasoning Pro Providers
Perplexity $2.00 (Cheapest)
Vercel $2.00 (Cheapest)
Benchmark Comparison
7
Benchmarks Compared
1
GPT-5 Codex Wins
0
Sonar Reasoning Pro Wins
Benchmark Scores
| Benchmark | GPT-5 Codex | Sonar Reasoning Pro | Winner |
|---|---|---|---|
Intelligence Index Overall intelligence score | 44.5 | 24.6 | |
Coding Index Code generation & understanding | 38.9 | - | - |
Math Index Mathematical reasoning | 98.7 | - | - |
MMLU Pro Academic knowledge | 86.5 | - | - |
GPQA Graduate-level science | 83.7 | - | - |
LiveCodeBench Competitive programming | 84.0 | - | - |
AIME Competition math | - | 79.0 | - |
GPT-5 Codex significantly outperforms in coding benchmarks.
Cost vs Quality
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GPT-5 Codex
Other models
Context & Performance
Context Window
GPT-5 Codex
400,000
tokens
Max output: 128,000 tokens
Sonar Reasoning Pro
128,000
tokens
GPT-5 Codex has a 68% larger context window.
Speed Performance
| Metric | GPT-5 Codex | Sonar Reasoning Pro | Winner |
|---|---|---|---|
| Tokens/second | 314.7 tok/s | 0.0 tok/s | |
| Time to First Token | 10.95s | 0.00s |
GPT-5 Codex responds Infinity% faster on average.
Capabilities
Feature Comparison
| Feature | GPT-5 Codex | Sonar Reasoning Pro |
|---|---|---|
| Vision (Image Input) | ||
| Tool/Function Calls | ||
| Reasoning Mode | ||
| Audio Input | ||
| Audio Output | ||
| PDF Input | ||
| Prompt Caching | ||
| Web Search |
License & Release
| Property | GPT-5 Codex | Sonar Reasoning Pro |
|---|---|---|
| License | Proprietary | Proprietary |
| Author | OpenAI | Perplexity |
| Released | Sep 2025 | Mar 2025 |
GPT-5 Codex Modalities
Input
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Output
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Sonar Reasoning Pro Modalities
Input
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Output
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