Data points: 132
The readout for GPT-5.3 Codex and GPT-OSS, before the detailed comparison sheet.
Decision read
GPT-OSS
GPT-OSS currently has the stronger profile, with verified wins split 2 to 4.
Evidence depth
132 data points
Includes 33 benchmark rows, 0 audit samples, and 8 provider examples.
Selection signal
Start with GPT-OSS
The charts below split 41 high-signal samples across speed, scores, and audit health.
Switch either side of this report to compare another model with the same LMSpeed data pipeline.
Select a different model to open a new comparison URL.
Model compare GPT-5.3 Codex vs GPT-OSSgpt-5-3-codex-vs-gpt-oss | Model A GPT-5.3 Codex | Model B GPT-OSS |
|---|---|---|
| Overall leader | Contender | Leading |
| Verified metric wins | 2 wins | 4 wins |
| Where it leads | Cheapest input price, Provider coverage | Average speed, First-token latency, Free providers, Recent tests |
Third-party benchmark profile synced into LMSpeed; only metrics available for both models are shown.
Compare benchmark category scores on a 0-100 scale. Select a category to inspect the gap.
Avg. score
GPT-5.3 Codex
67.1
Avg. score
GPT-OSS
57.1
Selected category
Agents
GPT-5.3 Codex leads by 27.5
Metric-level scores with benchmark source, rank depth, confidence, error, and evaluation date where available.
GPT-5.3 Codex
winner85.0
Rank #8/82 · confidence 1 · eval date 2026-02-05
GPT-OSS
34.0
Rank #60/82 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
83.6 tok/s
Rank #38/78 · confidence 4
GPT-OSS
winner324.3 tok/s
Rank #1/78 · confidence 4
GPT-5.3 Codex
67.20 s
Rank #74/78 · confidence 4
GPT-OSS
winner0.53 s
Rank #6/78 · confidence 4
GPT-5.3 Codex
67.20 s
Rank #71/78 · confidence 4
GPT-OSS
winner6.70 s
Rank #39/78 · confidence 4
GPT-5.3 Codex
$4.81/M
Rank #75/95 · confidence 4
GPT-OSS
winner$0.262/M
Rank #13/95 · confidence 4
GPT-5.3 Codex
$1.75/M
Rank #69/95 · confidence 4
GPT-OSS
winner$0.150/M
Rank #13/95 · confidence 4
GPT-5.3 Codex
$14.00/M
Rank #75/95 · confidence 4
GPT-OSS
winner$0.600/M
Rank #15/95 · confidence 4
GPT-5.3 Codex
winner74.0
Rank #4/57 · confidence 1 · eval date 2026-02-05
GPT-OSS
50.7
Rank #41/57 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner93.0
Rank #4/57 · confidence 1 · eval date 2026-02-05
GPT-OSS
30.2
Rank #47/57 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner16.9
Rank #6/44 · confidence 1 · eval date 2026-02-05
GPT-OSS
1.1
Rank #31/44 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner91.5%
Rank #6/103 · confidence 4
GPT-OSS
67.2%
Rank #73/103 · confidence 4
GPT-5.3 Codex
winner39.9%
Rank #8/103 · confidence 4
GPT-OSS
5.2%
Rank #73/103 · confidence 4
GPT-5.3 Codex
winner53.1
Rank #5/61 · confidence 1 · eval date 2026-02-05
GPT-OSS
28.6
Rank #41/61 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner53.0
Rank #5/59 · confidence 1 · eval date 2026-02-05
GPT-OSS
23.5
Rank #43/59 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner53.2
Rank #7/63 · confidence 1 · eval date 2026-02-05
GPT-OSS
38.9
Rank #40/63 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner53.2%
Rank #8/101 · confidence 4
GPT-OSS
36.0%
Rank #65/101 · confidence 4
GPT-5.3 Codex
winner86.7
Rank #10/69 · confidence 1 · eval date 2026-02-05
GPT-OSS
21.2
Rank #61/69 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner100.0
Rank #1/51 · confidence 1 · eval date 2026-02-05
GPT-OSS
26.3
Rank #44/51 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner51.8
Rank #3/58 · confidence 1 · eval date 2026-02-05
GPT-OSS
21.5
Rank #49/58 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner91.5
Rank #4/63 · confidence 1 · eval date 2026-02-05
GPT-OSS
78.2
Rank #40/63 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
86.9
Rank #16/58 · confidence 1 · eval date 2026-02-05
GPT-OSS
winner91.2
Rank #4/58 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner39.9
Rank #5/63 · confidence 1 · eval date 2026-02-05
GPT-OSS
18.5
Rank #33/63 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner44.3
Rank #6/66 · confidence 1 · eval date 2026-02-05
GPT-OSS
23.8
Rank #43/66 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner91.2
Rank #7/67 · confidence 1 · eval date 2026-02-05
GPT-OSS
44.5
Rank #52/67 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner96.9
Rank #5/50 · confidence 1 · eval date 2026-02-05
GPT-OSS
35.3
Rank #39/50 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner95.8
Rank #3/60 · confidence 1 · eval date 2026-02-05
GPT-OSS
18.9
Rank #53/60 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner1206.0
Rank #30/46 · confidence 1 · eval date 2026-02-05
GPT-OSS
1011.0
Rank #44/46 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner75.4
Rank #8/60 · confidence 1 · eval date 2026-02-05
GPT-OSS
69.0
Rank #26/60 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner91.4
Rank #11/56 · confidence 1 · eval date 2026-02-05
GPT-OSS
38.5
Rank #52/56 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner57.5
Rank #10/36 · confidence 1 · eval date 2026-02-05
GPT-OSS
29.6
Rank #34/36 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner76.9
Rank #12/69 · confidence 1 · eval date 2026-02-05
GPT-OSS
34.6
Rank #53/69 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner60.5
Rank #17/57 · confidence 1 · eval date 2026-02-05
GPT-OSS
37.9
Rank #38/57 · confidence 1 · eval date 2025-08-05
GPT-5.3 Codex
winner86.0
Rank #21/58 · confidence 1 · eval date 2026-02-05
GPT-OSS
65.8
Rank #39/58 · confidence 1 · eval date 2025-08-05
Latest completed audits from shared providers, with four safety and integrity score groups plus report links.
| Provider | GPT-5.3 Codex | GPT-OSS |
|---|---|---|
| No completed audits are available from shared providers yet. | ||
Speed aggregates and input/output pricing share each provider row for real API selection and migration cost checks.
| Provider | GPT-5.3 Codex | GPT-OSS |
|---|---|---|
55 tests | GPT-5.3 Codex speed / latency 38 tok/s / 4553ms input / output No data |
This report only uses LMSpeed data for GPT-5.3 Codex and GPT-OSS: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.
| Guidance | GPT-5.3 Codex | GPT-OSS |
|---|---|---|
| When to choose each model | GPT-5.3 Codex GPT-5.3 Codex is stronger when you prioritize Cheapest input price, Provider coverage. | GPT-OSS GPT-OSS is stronger when you prioritize Average speed, First-token latency, Free providers, Recent tests. |
TL;DR: GPT-OSS leads across 132 verifiable data points, including pricing, speed, latency, benchmarks, and provider examples.
Continue from GPT-5.3 Codex vs GPT-OSS into nearby model comparisons with enough verified LMSpeed data.
| Model metadata | GPT-5.3 Codex exposes 400K tokens; notable signals: Text input, Image input, File input, Text output. | GPT-OSS exposes 131.1K tokens; notable signals: Text input, Text output, Tool calling, Reasoning. |
|---|---|---|
| Developer | OpenAI | No data |
| Context window | 400K tokens | 131.1K tokens |
| Max output | 128K tokens | 131.1K tokens |
| Released | Feb 2026 | Aug 2025 |
| Modalities | Input TextImageFile Output Text | Input Text Output Text |
| Features | Text inputImage inputFile inputText outputTool callingStructured outputsJSON modeReasoning | Text inputText outputTool callingReasoning |
| Parameters | No data | 120B |
| Tokenizer | GPT | GPT |
| Knowledge cutoff | No data | 2024-06-30 |
| OpenRouter ID | openai/gpt-5.3-codex | openai/gpt-oss-120b:free |
| References | No data | No data |
GPT-OSS
speed / latency
164 tok/s / 1247ms
input / output
No data
OpenRouter40 tests | GPT-5.3 Codex speed / latency N/A / N/A input / output No data | GPT-OSS speed / latency 41 tok/s / 2851ms input / output No data |
|---|
素墨API35 tests | GPT-5.3 Codex speed / latency N/A / N/A input / output No data | GPT-OSS speed / latency 347 tok/s / 2670ms input / output No data |
|---|
钠 API25 tests | GPT-5.3 Codex speed / latency 63 tok/s / 3786ms input / output No data | GPT-OSS speed / latency 908 tok/s / 3109ms input / output No data |
|---|
Rnglg2 API20 tests | GPT-5.3 Codex speed / latency N/A / N/A input / output No data | GPT-OSS speed / latency 338 tok/s / 2317ms input / output No data |
|---|
GPT-5.3 Codex gpt-5.3-codex-openai-compact speed / latency No data input / output $75.00/M / $600.00/M | GPT-OSS gpt-oss:120b speed / latency No data input / output $0/M / $0/M |
GPT-5.3 Codex gpt-5.3-codex-spark speed / latency No data input / output $1.75/M / $14.00/M | GPT-OSS daipai/gpt-oss-120b speed / latency No data input / output $0.0010/M / $0.0010/M |
GPT-5.3 Codex gpt-5.3-codex speed / latency No data input / output $0.072/M / $0.575/M | GPT-OSS gpt-oss-120b speed / latency No data input / output $0.012/M / $0.103/M |
Rankings are based on community-submitted tests and periodic health probes. Advisory only, not official data.
