Gemini 1.5 Flash vs Gemini 1.5 Pro
Gemini 1.5 Pro significantly outperforms across most benchmarks. Gemini 1.5 Flash is 16.7x cheaper per token.
Google · Google · Updated for 2026
Which is better?
Gemini 1.5 Flash outperforms in 0 benchmarks, while Gemini 1.5 Pro is better at 22 benchmarks (AMC_2022_23, BIG-Bench Hard, FLEURS, FunctionalMATH, GPQA, GSM8k, HellaSwag, HiddenMath, HumanEval, MATH, MathVista, MGSM, MMLU, MMLU-Pro, MMMU, MRCR, Natural2Code, PhysicsFinals, Vibe-Eval, Video-MME, WMT23, XSTest). Gemini 1.5 Pro significantly outperforms across most benchmarks.
On price, Gemini 1.5 Flash is roughly 16.7x cheaper per token on a blended 3:1 input/output basis, which adds up quickly at production volume.
Gemini 1.5 Pro also accepts a larger context window (2,097,152 input tokens), making it the stronger choice for long documents and large codebases.
Based on current benchmark, pricing, and model metadata for 2026.
Choose Gemini 1.5 Flash
- cost matters — it's about 16.7x cheaper per token
Choose Gemini 1.5 Pro
- you want the strongest raw capability — it leads on 22 of 22 shared benchmarks
- you process long inputs — it offers a 2,097,152 token context window
At a glance
The differences that matter most.
Performance Benchmarks
Comparative analysis across standard metrics
Gemini 1.5 Flash outperforms in 0 benchmarks, while Gemini 1.5 Pro is better at 22 benchmarks (AMC_2022_23, BIG-Bench Hard, FLEURS, FunctionalMATH, GPQA, GSM8k, HellaSwag, HiddenMath, HumanEval, MATH, MathVista, MGSM, MMLU, MMLU-Pro, MMMU, MRCR, Natural2Code, PhysicsFinals, Vibe-Eval, Video-MME, WMT23, XSTest).
Gemini 1.5 Pro significantly outperforms across most benchmarks.
Arena Performance
Playground indexes and blind preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Gemini 1.5 Flash ($0.15/1M tokens) is 16.7x cheaper than Gemini 1.5 Pro ($2.50/1M tokens).
For output processing, Gemini 1.5 Flash ($0.60/1M tokens) is 16.7x cheaper than Gemini 1.5 Pro ($10.00/1M tokens).
In conclusion, Gemini 1.5 Pro 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 Pro accepts 2,097,152 input tokens compared to Gemini 1.5 Flash's 1,048,576 tokens. Both models can generate responses up to 8,192 tokens.
Input Capabilities
Supported data types and modalities
Both Gemini 1.5 Flash and Gemini 1.5 Pro support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Gemini 1.5 Flash
Gemini 1.5 Pro
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
Both models were released on 2024-05-01.
They likely represent similar generations of model development.
May 1, 2024
2.3 years ago
May 1, 2024
2.3 years ago
Knowledge Cutoff
When training data ends
Both models have the same knowledge cutoff date of 2023-11-01.
They should have similar awareness of historical events and information up to this date.
Nov 2023
Nov 2023
Provider Availability
Gemini 1.5 Flash is available from Google. Gemini 1.5 Pro is available from Google.
Gemini 1.5 Flash
Gemini 1.5 Pro
Outputs Comparison
Judge for yourself.
Run your own prompts against Gemini 1.5 Flash and Gemini 1.5 Pro side-by-side, then vote on the output you prefer.
FAQ
Common questions about Gemini 1.5 Flash vs Gemini 1.5 Pro.