Claude Sonnet 5 vs Gemini 3.5 Flash
Anthropic's mid-tier against Google's production / efficiency tier — published pricing, context windows and specs, side by side.
Claude Sonnet 5 vs Gemini 3.5 Flash: side-by-side
| Claude Sonnet 5 | Gemini 3.5 Flash | |
|---|---|---|
| Maker | Anthropic | |
| Released | 30 June 2026 | 19 May 2026 (Google I/O) |
| Tier | Mid-tier | Production / efficiency tier |
| Context window | 1,000,000 tokens (default & max) | 1,048,576 tokens |
| Max output | Up to 128,000 tokens | 65,536 tokens |
| API price (per 1M) | $2 / $10 intro (to 31 Aug 2026) · $3 / $15 standard | $1.50 / $9 per 1M tokens |
| Access | Proprietary — Claude API & claude.ai (default model on Free & Pro plans) | Proprietary — Gemini API (Google) |
| Best at | Agentic coding, high-volume production work, large-codebase tasks | Agentic coding, high-volume production work at near-Pro quality |
| Standout | 1M context by default; early-access partners report it finishes tasks earlier Sonnets stopped short on and checks its own output | Beats Gemini 3.1 Pro on coding at 25% lower cost — first public Gemini 3.5 release |
Price comparison
| Model | Input (per 1M) | Output (per 1M) |
|---|---|---|
| Claude Sonnet 5 (intro, to 31 Aug 2026) | $2.00 | $10.00 |
| Claude Sonnet 5 (standard, from 1 Sep 2026) | $3.00 | $15.00 |
| Gemini 3.5 Flash | $1.50 | $9.00 |
Published benchmark figures
Each figure below is the model's own published score as listed on its AI Model Hub page. Different suites (and suite versions) are not directly comparable.
| Model | Benchmark | Published score |
|---|---|---|
| Gemini 3.5 Flash | Terminal-Bench 2.1 | 76.2% |
| Gemini 3.5 Flash | MCP Atlas | 83.6% |
| Gemini 3.5 Flash | CharXiv Reasoning | 84.2% |
| Gemini 3.5 Flash | GPQA | 82.8% |
What the table says
- Pricing. Claude Sonnet 5 lists at $2 / $10 intro (to 31 Aug 2026) · $3 / $15 standard; Gemini 3.5 Flash lists at $1.50 / $9 per 1M tokens. On these published rates, Gemini 3.5 Flash's input price is 1.3x lower than Claude Sonnet 5's, and Gemini 3.5 Flash's output price is 1.1x lower than Claude Sonnet 5's. Claude Sonnet 5's standard rate card from 1 September 2026 is $3 / $15 per 1M tokens. Cached input for Gemini 3.5 Flash lists at $0.15 per 1M tokens.
- Context. Both are in the same context class: Claude Sonnet 5 lists 1,000,000 tokens (default & max) and Gemini 3.5 Flash lists 1,048,576 tokens.
- Access. Both are proprietary, hosted-API models; neither publishes weights for self-hosting.
- Benchmarks. The two model pages report results on different benchmark suites, so the published scores are not directly comparable head-to-head; the tables below list each model's own published figures.
Key takeaway
Everything above is drawn from the two models' published rate cards and spec sheets. Which one fits depends on the workload you price it against — run your own token volumes through the pricing calculator to see the monthly difference.
Full Claude Sonnet 5 overview Full Gemini 3.5 Flash overview
Frequently asked questions
Which is cheaper, Claude Sonnet 5 or Gemini 3.5 Flash?
Gemini 3.5 Flash — it lists at $1.50 / $9 per 1M tokens versus $2 / $10 intro (to 31 Aug 2026) · $3 / $15 standard for Claude Sonnet 5.
Which has the bigger context window, Claude Sonnet 5 or Gemini 3.5 Flash?
They are in the same class: Claude Sonnet 5 lists 1,000,000 tokens (default & max) and Gemini 3.5 Flash lists 1,048,576 tokens.
Which model is newer?
Claude Sonnet 5 is the more recent release (30 June 2026); Gemini 3.5 Flash was released 19 May 2026 (Google I/O).
Can I run Claude Sonnet 5 or Gemini 3.5 Flash locally?
No — both Claude Sonnet 5 and Gemini 3.5 Flash are proprietary models accessed through their vendors' APIs and apps; neither publishes weights.