Claude Sonnet 5.5 vs Gemini 3.5 Flash: price, context window and capabilities
Claude Sonnet 5.5 (anthropic/claude-sonnet-5.5) from Anthropic and Gemini 3.5 Flash (google/gemini-3.5-flash) from Google are both multimodal language models on the OceanToken API. Gemini 3.5 Flash costs less per token than Claude Sonnet 5.5: $1.35 against $1.80 per 1M input tokens (25% less) and $8.10 against $9.00 per 1M output tokens (10% less). Both are 10% off their official price on OceanToken, for every account. Gemini 3.5 Flash has the larger context window: 1.05M tokens (1,048,576) against 1M (1,000,000) for Claude Sonnet 5.5. Both support tool calling, reasoning, structured outputs, image input and file input; only Gemini 3.5 Flash also lists audio input and video input.
Side by side
| Spec | Claude Sonnet 5.5 −10% | Gemini 3.5 Flash −10% |
|---|---|---|
| Model | Claude Sonnet 5.5anthropic/ | Gemini 3.5 Flashgoogle/ |
| Publisher | Anthropic | |
| Kind | Text & vision | Text, vision, audio & video |
| Context window | 1M tokens1,000,000 | 1.05M tokens1,048,576 |
| Input price | $1.80 / 1M tokens | $1.35 / 1M tokens |
| Output price | $9.00 / 1M tokens | $8.10 / 1M tokens |
| Cached input price | $0.10 / 1M tokens | $0.15 / 1M tokens |
| Cache write price | $2.50 / 1M tokens | $1.583 / 1M tokens |
| Web search price | $0.01 / search | $0.014 / search |
| Discount (vs official, top tier) | −10% | −10% |
| Inputs | text, images and files | text, images, files, audio and video |
| Outputs | text | text |
| Tool calling | Yes | Yes |
| Reasoning | Yes | Yes |
| Structured outputs | Yes | Yes |
About these prices
Which should you choose?
- Choose Gemini 3.5 Flash to spend less per token: 25% less for input and 10% less for output than Claude Sonnet 5.5.
- Choose Gemini 3.5 Flash for the longest inputs: its context window holds 1.05M tokens against 1M for Claude Sonnet 5.5.
- Choose Gemini 3.5 Flash if you need audio input and video input: Claude Sonnet 5.5 does not list them.
- Not sure? Call both with the same OceanToken API key and compare them on your own prompts; each request is billed per use from one prepaid balance.
Get API Key Claude Sonnet 5.5 Gemini 3.5 Flash
Frequently asked questions
Which is cheaper, Claude Sonnet 5.5 or Gemini 3.5 Flash?
Gemini 3.5 Flash. Gemini 3.5 Flash costs less per token than Claude Sonnet 5.5: $1.35 against $1.80 per 1M input tokens (25% less) and $8.10 against $9.00 per 1M output tokens (10% less). Both are 10% off their official price on OceanToken, for every account. The OceanToken console always shows the current price.
Which has the larger context window, Claude Sonnet 5.5 or Gemini 3.5 Flash?
Gemini 3.5 Flash. Gemini 3.5 Flash has the larger context window: 1.05M tokens (1,048,576) against 1M (1,000,000) for Claude Sonnet 5.5.
Can I call both Claude Sonnet 5.5 and Gemini 3.5 Flash with one API key?
Yes. Both are on the OceanToken API at https://api.oceantoken.ai/v1: one API key and one prepaid balance call either model. Send the model id anthropic/claude-sonnet-5.5 or google/gemini-3.5-flash.
Models and publishers
Claude Sonnet 5.5 · Gemini 3.5 Flash · All Anthropic models · All Google models
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