Model comparison
GPT-5.3 Codex vs Sonar
GPT-5.3 Codex is the stronger model overall, scoring 45.5 to 37.8 on the Noometry Index. Sonar costs 4.8× less per token, which makes it the better buy when GPT-5.3 Codex's lead doesn't matter for your workload.
Last verified . 0 shared benchmarks.
PerplexitySummary
- The widest gap is in coding, where GPT-5.3 Codex leads 48.5 to 35.1.
- Sonar is cheaper at $1 / $1 per million input/output tokens, against $1.75 / $14 for GPT-5.3 Codex.
- GPT-5.3 Codex accepts more context: 400K tokens versus 128K.
Side by side
| GPT-5.3 Codex | Sonar | |
|---|---|---|
| Provider | OpenAI | Perplexity |
| Noometry Index | 45.5 | 37.8 |
| Released | 2026-02-05 | 2024-01-01 |
| Weights | Proprietary | Proprietary |
| Context window | 400K | 128K |
| Max output | 128K | 4K |
| Input $ / M tokens | $1.75 | $1 |
| Output $ / M tokens | $14 | $1 |
| Results tracked | 8 | 7 |
Sponsored placements are available on pages like this one. Advertise on Noometry
Category by category
Coding GPT-5.3 Codex leads
GPT-5.3 Codex: 48.5 (#51), Sonar: 35.1 (#217)
| Benchmark | GPT-5.3 Codex | Sonar |
|---|---|---|
| SWE-bench Verified | 74.8% | — |
| LMArena WebDev | 1408 | — |
| WeirdML | 79.3% | — |
| LiveBench Coding | — | 35.1% |
| ALE-Bench | 1,655 | — |
Agentic & Tool Use Not comparable
GPT-5.3 Codex: 47.8 (#9), Sonar: —
| Benchmark | GPT-5.3 Codex | Sonar |
|---|---|---|
| Terminal-Bench | 78.4% | — |
| METR Time Horizons | 74.5% | — |
| Vending-Bench 2 | 5,940 | — |
Reasoning Not comparable
GPT-5.3 Codex: —, Sonar: 20.3 (#221)
| Benchmark | GPT-5.3 Codex | Sonar |
|---|---|---|
| LiveBench Reasoning | — | 46.3% |
| LiveBench Data Analysis | — | 37.9% |
| Epoch Capabilities Index | 156.84 | — |
| LiveBench | — | 46.9% |
Math Not comparable
GPT-5.3 Codex: —, Sonar: 31.3 (#197)
| Benchmark | GPT-5.3 Codex | Sonar |
|---|---|---|
| LiveBench Math | — | 41.6% |
Instruction Following Not comparable
GPT-5.3 Codex: —, Sonar: 71.5 (#146)
| Benchmark | GPT-5.3 Codex | Sonar |
|---|---|---|
| LiveBench Instruction Following | — | 76.2% |
Writing & Preference Not comparable
GPT-5.3 Codex: —, Sonar: 52.6 (#166)
| Benchmark | GPT-5.3 Codex | Sonar |
|---|---|---|
| LiveBench Language | — | 44.1% |
Frequently asked questions
Is GPT-5.3 Codex better than Sonar?
GPT-5.3 Codex is the stronger model overall, scoring 45.5 to 37.8 on the Noometry Index. Sonar costs 4.8× less per token, which makes it the better buy when GPT-5.3 Codex's lead doesn't matter for your workload.
Which is cheaper, GPT-5.3 Codex or Sonar?
Sonar is cheaper. It lists at $1 per million input tokens and $1 per million output tokens; GPT-5.3 Codex lists at $1.75 and $14.
Is GPT-5.3 Codex or Sonar better for coding?
GPT-5.3 Codex scores higher on coding benchmarks: 48.5 versus 35.1 in the Noometry coding category.
Which has the bigger context window?
GPT-5.3 Codex does, with 400K tokens against 128K.
How many benchmarks do GPT-5.3 Codex and Sonar share?
0 benchmarks have published results for both models. GPT-5.3 Codex has 8 scored results on Noometry and Sonar has 7.