Data points: 66
Model compare
The readout for Gemini 1.5 Flash and GPT-5.1, before the detailed comparison sheet.
Weighted outcome: GPT-5.1. Benchmark capability categories carry 80%, while price, API performance, and availability carry 20%.
Decision read
GPT-5.1
GPT-5.1 has the higher weighted result; Model A / B score 8 to 92.
Evidence depth
66 data points
Includes 5 benchmark rows, 0 audit samples, and 7 provider examples.
Selection signal
Start with GPT-5.1
The charts below split 12 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.
This report only uses LMSpeed data for Gemini 1.5 Flash and GPT-5.1: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.
| Model compare | Gemini 1.5 Flash | GPT-5.1 |
|---|---|---|
| Overall leader | Contender | Leading |
| Weighted overall score | 8.0 pts | 92.0 pts |
| Benchmark category leads | 0 categories | 3 categories |
| Operational advantages | Average speed, First-token latency | Cheapest input price, Free providers, Provider coverage |
| Context window | No data | 400K tokens |
| Max output | No data | 128K tokens |
| Modalities | No data | Input ImageTextFile Output Text |
The overall result weights benchmark capability categories at 80% and price, API speed/latency, and availability at 20%. Recent test volume does not affect the winner, and missing benchmark categories are excluded.
| Model compare | Gemini 1.5 Flash | GPT-5.1 |
|---|---|---|
| Developer | OpenAI | |
| Released | No data | Nov 2025 |
| Parameters | No data | No data |
| Tokenizer | No data | GPT |
| Knowledge cutoff | No data | No data |
| OpenRouter ID | No data | openai/gpt-5.1 |
| References | No data | No data |
This report only uses LMSpeed data for Gemini 1.5 Flash and GPT-5.1: pricing, speed aggregates, third-party benchmark scores, and shared provider samples.
Gemini 1.5 Flash
Gemini 1.5 Flash has these operational advantages: Average speed, First-token latency.
GPT-5.1
GPT-5.1 is stronger in benchmark categories (Coding, Reasoning, Math) and operational dimensions (Cheapest input price, Free providers, Provider coverage).
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
Gemini 1.5 Flash
37.7
Avg. score
GPT-5.1
52
GPT-5.1
GPT-5.1 leads by 16.0
GPT-5.1 leads by 15.2
GPT-5.1
GPT-5.1 leads by 11.5
No data
No data
GPT-5.1
Metric-level scores with benchmark source, rank depth, confidence, error, and evaluation date where available.
Gemini 1.5 Flash
68.0%
Rank #109/125 · confidence 4
GPT-5.1
winner87.0%
Rank #12/125 · confidence 4
Gemini 1.5 Flash
46.3%
Rank #170/188 · confidence 4
GPT-5.1
winner87.3%
Rank #33/188 · confidence 4
Gemini 1.5 Flash
3.5%
Rank #177/187 · confidence 4
GPT-5.1
winner26.5%
Rank #40/187 · confidence 4
Gemini 1.5 Flash
27.3%
Rank #95/115 · confidence 4
GPT-5.1
winner86.8%
Rank #4/115 · confidence 4
Gemini 1.5 Flash
26.7%
Rank #153/185 · confidence 4
GPT-5.1
winner43.3%
Rank #42/185 · confidence 4
Latest completed audits from shared providers, with four safety and integrity score groups plus report links.
| Provider | Gemini 1.5 Flash | GPT-5.1 |
|---|---|---|
| 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 | Gemini 1.5 Flash | GPT-5.1 |
|---|---|---|
15 tests | Gemini 1.5 Flash speed / latency 163 tok/s / 1183ms input / output No data | GPT-5.1 speed / latency N/A / N/A input / output No data |
0 tests | Gemini 1.5 Flash speed / latency N/A / N/A input / output No data | GPT-5.1 speed / latency N/A / N/A input / output No data |
0 tests | Gemini 1.5 Flash speed / latency N/A / N/A input / output No data | GPT-5.1 speed / latency N/A / N/A input / output No data |
0 tests | Gemini 1.5 Flash speed / latency N/A / N/A input / output No data | GPT-5.1 speed / latency N/A / N/A input / output No data |
0 tests | Gemini 1.5 Flash speed / latency N/A / N/A input / output No data | GPT-5.1 speed / latency N/A / N/A input / output No data |
Gemini 1.5 Flash gemini-1.5-flash-latest speed / latency No data input / output $0.113/M/$0.450/M | GPT-5.1 gpt-5.1-chat-2025-11-13 speed / latency No data input / output $7.88/M | |
Gemini 1.5 Flash gemini-1.5-flash-latest speed / latency No data input / output $0.734/M/$2.94/M | GPT-5.1 gpt-5.1-2025-11-13 speed / latency No data input / output $2.14/M |
Weighted outcome: GPT-5.1. Benchmark capability categories carry 80%, while price, API performance, and availability carry 20%.
| Features | None listed | Text inputImage inputFile inputText outputTool callingStructured outputsJSON modeReasoning |
|---|
