Gemini 1.5 Flash vs o1-preview
o1-preview leads the LLM Stats Score 16.7 to 6.1. Gemini 1.5 Flash is 100.0x cheaper per token.
Google · OpenAI · Updated for 2026
Which is better?
o1-preview leads the overall LLM Stats Score 16.7 to 6.1, ranking #208 overall.
In the 4 individual benchmarks reported for both models, o1-preview wins 4; this is a narrower head-to-head signal than the composite indexes.
On price, Gemini 1.5 Flash is roughly 100.0x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Gemini 1.5 Flash also accepts a larger context window (1,048,576 input tokens), making it the stronger choice for long documents and large codebases.
Based on current LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose Gemini 1.5 Flash
- cost matters — it's about 100.0x cheaper per token
- you process long inputs — it offers a 1,048,576 token context window
Choose o1-preview
- overall performance matters — it scores 16.7 and ranks #208 on LLM Stats
- your work emphasizes reasoning — it leads those capability indexes
- you value its reported benchmark strengths — it wins 4 of 4 exact shared results
- you want the most recent training data — it shipped Sep 2024
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
Individual benchmarks
22 reported for Gemini 1.5 Flash · 8 for o1-preview
Gemini 1.5 Flash outperforms in 0 benchmarks, while o1-preview is better at 4 benchmarks (GPQA, MATH, MGSM, MMLU).
o1-preview significantly outperforms across most benchmarks.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Gemini 1.5 Flash ($0.15/1M tokens) is 100.0x cheaper than o1-preview ($15.00/1M tokens).
For output processing, Gemini 1.5 Flash ($0.60/1M tokens) is 100.0x cheaper than o1-preview ($60.00/1M tokens).
In conclusion, o1-preview is more expensive than Gemini 1.5 Flash.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
Gemini 1.5 Flash accepts 1,048,576 input tokens compared to o1-preview's 128,000 tokens. o1-preview can generate longer responses up to 32,768 tokens, while Gemini 1.5 Flash is limited to 8,192 tokens.
Input capabilities
Documented input modalities across available providers
Gemini 1.5 Flash supports multimodal inputs, whereas o1-preview does not.
Gemini 1.5 Flash can handle both text and other forms of data like images, making it suitable for multimodal applications.
Gemini 1.5 Flash
o1-preview
License
Usage and distribution terms
Both models are licensed under proprietary licenses.
Both models have usage restrictions defined by their respective organizations.
Proprietary
Closed source
Proprietary
Closed source
Release Timeline
When each model was launched
Gemini 1.5 Flash was released on 2024-05-01, while o1-preview was released on 2024-09-12.
o1-preview is 4 months newer than Gemini 1.5 Flash.
May 1, 2024
2.3 years ago
Sep 12, 2024
2.0 years ago
4mo newerKnowledge Cutoff
When training data ends
Gemini 1.5 Flash has a documented knowledge cutoff of 2023-11-01, while o1-preview's cutoff date is not specified.
We can confirm Gemini 1.5 Flash's training data extends to 2023-11-01, but cannot make a direct comparison without o1-preview's cutoff date.
Nov 2023
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Provider Availability
Gemini 1.5 Flash is available from Google. o1-preview is available from OpenAI, Azure.
Gemini 1.5 Flash
o1-preview
Outputs Comparison
Judge for yourself.
Run your own prompts against Gemini 1.5 Flash and o1-preview side-by-side, then vote on the output you prefer.
FAQ
Common questions about Gemini 1.5 Flash vs o1-preview.