Claude Sonnet 5.5 vs Gemini 1.5 Pro
Claude Sonnet 5.5 leads the LLM Stats Score 51.5 to 12.0. Claude Sonnet 5.5 is 1.1x cheaper per token.
Anthropic · Google · Updated for 2026
Which is better?
Claude Sonnet 5.5 leads the overall LLM Stats Score 51.5 to 12.0, ranking #12 overall.
On price, Claude Sonnet 5.5 is roughly 1.1x 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 LLM Stats indexes, shared benchmarks, pricing, and model metadata for 2026.
Choose Claude Sonnet 5.5
- overall performance matters — it scores 51.5 and ranks #12 on LLM Stats
- your work emphasizes reasoning and coding — it leads those capability indexes
- cost matters — it's about 1.1x cheaper per token
- you want the most recent training data — it shipped Sep 2026
Choose Gemini 1.5 Pro
- you process long inputs — it offers a 2,097,152 token context window
At a glance
The differences that matter most.
Individual benchmarks
8 reported for Claude Sonnet 5.5 · 23 for Gemini 1.5 Pro
Claude Sonnet 5.5 and Gemini 1.5 Prodon't have any common benchmark datasets to compare. They may have been evaluated on different testing suites.
Human preference
Blind head-to-head votes and playground preference scores
Pricing Analysis
Price comparison per million tokens
For input processing, Claude Sonnet 5.5 ($2.00/1M tokens) is 1.3x cheaper than Gemini 1.5 Pro ($2.50/1M tokens).
For output processing, Claude Sonnet 5.5 ($10.00/1M tokens) costs the same as Gemini 1.5 Pro ($10.00/1M tokens).
In conclusion, Gemini 1.5 Pro is more expensive than Claude Sonnet 5.5.*
* 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 Claude Sonnet 5.5's 1,000,000 tokens. Claude Sonnet 5.5 can generate longer responses up to 128,000 tokens, while Gemini 1.5 Pro is limited to 8,192 tokens.
Input capabilities
Documented input modalities across available providers
Both Claude Sonnet 5.5 and Gemini 1.5 Pro support multimodal inputs.
They are both capable of processing various types of data, offering versatility in application.
Claude Sonnet 5.5
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
Claude Sonnet 5.5 was released on 2026-09-28, while Gemini 1.5 Pro was released on 2024-05-01.
Claude Sonnet 5.5 is 29 months newer than Gemini 1.5 Pro.
Sep 28, 2026
0 days ago
2.4yr newerMay 1, 2024
2.4 years ago
Knowledge Cutoff
When training data ends
Claude Sonnet 5.5 has a knowledge cutoff of 2026-06-01, while Gemini 1.5 Pro has a cutoff of 2023-11-01.
Claude Sonnet 5.5 has more recent training data (up to 2026-06-01), making it potentially better informed about events through that date compared to Gemini 1.5 Pro (2023-11-01).
Jun 2026
2.6 yr newerNov 2023
Provider Availability
Claude Sonnet 5.5 is available from Anthropic. Gemini 1.5 Pro is available from Google.
Claude Sonnet 5.5
Gemini 1.5 Pro
Outputs Comparison
Judge for yourself.
Run your own prompts against Claude Sonnet 5.5 and Gemini 1.5 Pro side-by-side, then vote on the output you prefer.
FAQ
Common questions about Claude Sonnet 5.5 vs Gemini 1.5 Pro.