Gemini 3.5 Flash vs GPT-5.5
GPT-5.5 leads the LLM Stats Score 47.2 to 42.0. Gemini 3.5 Flash is 3.3x cheaper per token.
Google · OpenAI · Updated for 2026
Which is better?
GPT-5.5 leads the overall LLM Stats Score 47.2 to 42.0, ranking #31 overall.
In the 14 individual benchmarks reported for both models, GPT-5.5 wins 10; this is a narrower head-to-head signal than the composite indexes.
On price, Gemini 3.5 Flash is roughly 3.3x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
GPT-5.5 also accepts a larger context window (1,050,000 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 3.5 Flash
- cost matters — it's about 3.3x cheaper per token
- you want the most recent training data — it shipped May 2026
Choose GPT-5.5
- overall performance matters — it scores 47.2 and ranks #31 on LLM Stats
- you value its reported benchmark strengths — it wins 10 of 14 exact shared results
- you process long inputs — it offers a 1,050,000 token context window
At a glance
The differences that matter most.
Capability indexes
Additional strengths measured across groups of related public benchmarks
1 more shared indexes
Individual benchmarks
16 reported for Gemini 3.5 Flash · 28 for GPT-5.5
Gemini 3.5 Flash outperforms in 4 benchmarks (Finance Agent v2, MCP Atlas, MMMU-Pro, Toolathlon), while GPT-5.5 is better at 10 benchmarks (ARC-AGI v2, DeepSWE 1.1, Finance Agent, Humanity's Last Exam, Legal Agent Benchmark, LiveBench, MRCR v2 (8-needle), OSWorld-Verified, SWE-Bench Pro, Terminal-Bench 2.0).
GPT-5.5 shows notably better performance in the majority of benchmarks.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Gemini 3.5 Flash ($1.50/1M tokens) is 3.3x cheaper than GPT-5.5 ($5.00/1M tokens).
For output processing, Gemini 3.5 Flash ($9.00/1M tokens) is 3.3x cheaper than GPT-5.5 ($30.00/1M tokens).
In conclusion, GPT-5.5 is more expensive than Gemini 3.5 Flash.*
* Using a 3:1 ratio of input to output tokens
Context Window
Maximum input and output token capacity
GPT-5.5 accepts 1,050,000 input tokens compared to Gemini 3.5 Flash's 1,000,000 tokens. Gemini 3.5 Flash can generate longer responses up to 1,000,000 tokens, while GPT-5.5 is limited to 128,000 tokens.
Input capabilities
Documented input modalities across available providers
Both Gemini 3.5 Flash and GPT-5.5 support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Gemini 3.5 Flash
GPT-5.5
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 3.5 Flash was released on 2026-05-19, while GPT-5.5 was released on 2026-04-23.
Gemini 3.5 Flash is 1 month newer than GPT-5.5.
May 19, 2026
4 months ago
3w newerApr 23, 2026
5 months ago
Knowledge Cutoff
When training data ends
Gemini 3.5 Flash has a knowledge cutoff of 2026-01-31, while GPT-5.5 has a cutoff of 2025-12-01.
Gemini 3.5 Flash has more recent training data (up to 2026-01-31), making it potentially better informed about events through that date compared to GPT-5.5 (2025-12-01).
Jan 2026
1 mo newerDec 2025
Provider Availability
Gemini 3.5 Flash is available from DeepInfra, Google. GPT-5.5 is available from OpenAI.
Gemini 3.5 Flash
GPT-5.5
Outputs Comparison
Judge for yourself.
Run your own prompts against Gemini 3.5 Flash and GPT-5.5 side-by-side, then vote on the output you prefer.
FAQ
Common questions about Gemini 3.5 Flash vs GPT-5.5.