Claude Sonnet 3.5 v2 vs Gemini 2.5 Pro vs Gemini 2.0 Flash
Gemini 2.5 Pro comes out ahead, 76 to 65 and 54 on our weighted score, and it is the cheaper option too.
AnthropicClaude Sonnet 3.5 v2
54/100- ECI133.5
- Price$3.00 / $15.00
- Context200K
- Our pick
GoogleGemini 2.5 Pro
76/100- ECI145.3
- Price$1.25 / $10.00
- Context1.05M
- Google
Gemini 2.0 Flash
65/100- ECI134.7
- Price—
- Context1.05M
Gemini 2.5 Pro is our pick
Gemini 2.5 Pro is the better all-round choice, scoring 76/100 against Gemini 2.0 Flash (65) and Claude Sonnet 3.5 v2 (54). It leads on capability and inputs & features. The score weighs capability 67%, inputs & features 20%, context window 13%.
- CapabilityGemini 2.5 ProCapabilities Index (ECI): Gemini 2.5 Pro 145.3 · Gemini 2.0 Flash 134.7 · Claude Sonnet 3.5 v2 133.5
- Lowest priceGemini 2.5 ProGemini 2.5 Pro $3.44 · Claude Sonnet 3.5 v2 $6.00 per 1M tokens (3:1 blend) · Gemini 2.0 Flash unpriced
- Longest contextGemini 2.5 Pro and Gemini 2.0 FlashGemini 2.5 Pro 1,048,576 · Gemini 2.0 Flash 1,048,576 · Claude Sonnet 3.5 v2 200,000 tokens
- Widest inputsGemini 2.5 Pro and Gemini 2.0 FlashClaude Sonnet 3.5 v2: Text, Images, PDFs · Gemini 2.5 Pro: Text, Images, PDFs, Audio, Video · Gemini 2.0 Flash: Text, Images, PDFs, Audio, Video
- Self-hostingNo open weightsAll three are available only through APIs
| Measure | Weight | Claude Sonnet 3.5 v2 | Gemini 2.5 Pro | Gemini 2.0 Flash |
|---|---|---|---|---|
| CapabilityCapabilities Index (ECI) | 67% | 57 | 72 | 59 |
| Inputs & features | 20% | 60 | 100 | 90 |
| Context window | 13% | 32 | 61 | 61 |
| Overall | 100% | 54/100 | 76/100 | 65/100 |
Left out because at least one model lacks the data: price. The remaining weights were rescaled.
Every spec in one table
Highlighted cells lead their row. Dashes mean the data is not published.
| Specification | Claude Sonnet 3.5 v2Anthropic | Gemini 2.5 ProGoogle | Gemini 2.0 FlashGoogle |
|---|---|---|---|
| Capability | |||
| Capabilities Index (ECI) | 133.5 | 145.3 (best) | 134.7 |
| ECI rank | #119 of 148 | #78 of 148 (best) | #116 of 148 |
| GPQA DiamondGraduate-level science questions | 55.3% | 85.3% (best) | — |
| FrontierMath Tiers 1–3Research-level mathematics | — | 24.6% | — |
| OTIS Mock AIME 2024–2025Competition mathematics | 8.5% | 84.7% (best) | — |
| SWE-bench VerifiedFixing real GitHub issues | — | 57.6% | — |
| Price per million tokens | |||
| Input | $3.00 | $1.25 (best) | — |
| Output | $15.00 | $10.00 (best) | — |
| Cached input | — | $0.125 | — |
| Blended (3:1) | $6.00 | $3.44 (best) | — |
| Long-context rate | Same rate | Over 200K: $2.50 / $15.00 | — |
| Price source | Median of 1 providers | Official Google API | — |
| Limits | |||
| Context window | 200,000 tokens | 1,048,576 tokens (best) | 1,048,576 tokens (best) |
| Max output | 8,192 tokens | 65,536 tokens (best) | 8,192 tokens |
| Inputs and features | |||
| Text | Yes | Yes | Yes |
| Images | Yes | Yes | Yes |
| PDFs | Yes | Yes | Yes |
| Audio | No | Yes | Yes |
| Video | No | Yes | Yes |
| Reasoning | No | Yes | No |
| Tool calling | Yes | Yes | Yes |
| Structured output | No | Yes | Yes |
| Availability | |||
| Weights | Proprietary | Proprietary | Proprietary |
| API model ID | — | gemini-2.5-pro | — |
| API providers | 1 | 22 (best) | — |
| Released | Oct 22, 2024 | Jun 17, 2025 | Dec 11, 2024 |
| Knowledge cutoff | Apr 30, 2024 | Jan 2025 | Jun 2024 |
What would a month cost?
Enter your expected volume in millions of tokens. List prices only; caching and batch discounts would lower these.
- Claude Sonnet 3.5 v2$60.00
- Gemini 2.5 Pro$32.50
- Gemini 2.0 Flash—
Which should you choose?
Which is better: Claude Sonnet 3.5 v2, Gemini 2.5 Pro or Gemini 2.0 Flash?
Gemini 2.5 Pro is the better all-round choice, scoring 76/100 against Gemini 2.0 Flash (65) and Claude Sonnet 3.5 v2 (54). It leads on capability and inputs & features. The score weighs capability 67%, inputs & features 20%, context window 13%.
Which is cheaper, Claude Sonnet 3.5 v2, Gemini 2.5 Pro or Gemini 2.0 Flash?
Gemini 2.5 Pro is cheaper at $1.25 input / $10.00 output per million tokens (official Google API price). Claude Sonnet 3.5 v2 costs $3.00 input / $15.00 output per million tokens (median across 1 API provider). At a typical mix of three input tokens to one output token, that is $3.44 per million tokens for Gemini 2.5 Pro versus $6.00 for Claude Sonnet 3.5 v2 (1.7× as much). Gemini 2.0 Flash has no published per-token price.
Which scores higher on benchmarks?
Gemini 2.5 Pro scores higher on the Capabilities Index (ECI): Gemini 2.5 Pro 145.3 (#78 of 148), Gemini 2.0 Flash 134.7 (#116 of 148) and Claude Sonnet 3.5 v2 133.5 (#119 of 148). Their confidence ranges do not overlap (143.6–146.9 vs 124.3–136.7), so the gap is a real one.
Which is better for coding?
There are no published SWE-bench Verified results for Claude Sonnet 3.5 v2 and Gemini 2.0 Flash yet, so there is no like-for-like coding score. On overall capability, Gemini 2.5 Pro leads, which tends to carry over to coding, but test on your own codebase. All three support tool calling for agent workflows.
Which has the bigger context window?
Gemini 2.5 Pro and Gemini 2.0 Flash have the largest context windows (1,048,576 and 1,048,576 tokens), against 200,000 for Claude Sonnet 3.5 v2. Maximum output per response: Claude Sonnet 3.5 v2 up to 8,192, Gemini 2.5 Pro up to 65,536, Gemini 2.0 Flash up to 8,192 tokens.
Which can read images, PDFs, audio or video?
Claude Sonnet 3.5 v2 accepts text, images and PDFs; Gemini 2.5 Pro accepts text, images, PDFs, audio and video; Gemini 2.0 Flash accepts text, images, PDFs, audio and video. Gemini 2.5 Pro handles the widest range of inputs.
Are any of these open source?
No. Claude Sonnet 3.5 v2, Gemini 2.5 Pro and Gemini 2.0 Flash are proprietary and only available through APIs and apps.
Which is newer?
Gemini 2.5 Pro is the newest, released Jun 17, 2025. Gemini 2.0 Flash came out Dec 11, 2024; Claude Sonnet 3.5 v2 came out Oct 22, 2024. Knowledge cutoff: Claude Sonnet 3.5 v2 Apr 30, 2024, Gemini 2.5 Pro Jan 2025, Gemini 2.0 Flash Jun 2024.
How do you decide the winner?
Each model gets a 0–100 score on capability (50%, independent benchmark results); price (25%, blended price per million tokens (3 input : 1 output), log scale); inputs & features (15%, image, PDF, audio and video input, tool calling, structured output and reasoning); context window (10%, maximum tokens per request, log scale). Dimensions missing for any model are dropped and the remaining weights rescaled, so every model is judged on the same evidence. Specs and prices come from public model listings and the labs’ own API pages; capability scores come from independent benchmark runs. Data updated Oct 4, 2026.
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