Claude Opus 4 vs Gemini 2.5 Flash
A complete head-to-head: pricing, context window, benchmarks, modality coverage, and openness, with a programmatic verdict synthesized from the underlying data.
- PriceGemini 2.5 Flash
Gemini 2.5 Flash is roughly 250.0× cheaper on output tokens ($0.30 vs $75.00 per 1M).
- Context windowGemini 2.5 Flash
Gemini 2.5 Flash accepts 1.0M tokens vs 200K, 5.2× the room for long documents and codebases.
- BenchmarksTie
No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores.
- ModalitiesGemini 2.5 Flash
Gemini 2.5 Flash supports 3 modalities (text, vision, audio) vs 2 for Claude Opus 4.
- OpennessTie
Both are closed-weight, API-only.
On balance Gemini 2.5 Flash edges ahead, winning 3 of 5 categories against Claude Opus 4's 0. Gemini 2.5 Flash is roughly 250.0× cheaper on output tokens ($0.30 vs $75.00 per 1M). Gemini 2.5 Flash accepts 1.0M tokens vs 200K, 5.2× the room for long documents and codebases.
No directly comparable public benchmarks are available for both models, check the spec sheets for individual scores. They differ in modality coverage, Claude Opus 4 handles text, vision while Gemini 2.5 Flash handles text, vision, audio, which can be the deciding factor before you even look at benchmarks. Both are closed-weight, API-only.
Claude Opus 4 is the newer of the two, released 1 months after Gemini 2.5 Flash, which usually means a more recent knowledge cutoff and updated safety post-training. Claude Opus 4 is usually picked for coding llm and coding agent workloads, while Gemini 2.5 Flash sees more deployments in rag and long context. If pricing matters more than every last benchmark point, run the numbers in the calculator below before committing.
Side-by-side specs
| Spec | Claude Opus 4 | Gemini 2.5 Flash |
|---|---|---|
| Provider | Anthropic | |
| Released | May 2025 | Apr 2025 |
| Modalities | text, vision | text, vision, audio |
| Context window | 200K tokens | 1.0M tokens |
| Max output | , | , |
| Input · 1M | $15.00 / 1M tokens | $0.075 / 1M tokens |
| Output · 1M | $75.00 / 1M tokens | $0.30 / 1M tokens |
| Knowledge cutoff | 2025-03 | 2025-01 |
| Open weights | No | No |
| API available | Yes | Yes |
Pricing at scale
What you'd actually pay at typical workloads. Numbers come from each model's published per-million-token rates.
- Light usage, 100k in / 50k out per day$158 vs $0.675
- Heavy usage, 1M in / 500k out per day$1,575 vs $6.75
- RAG workload, 5M in / 200k out per day$2,700 vs $13.05
Light usage, 100k in / 50k out per day: $158 vs $0.675 per month, model B comes out ahead. Heavy usage, 1M in / 500k out per day: $1,575 vs $6.75 per month, model B comes out ahead. RAG workload, 5M in / 200k out per day: $2,700 vs $13.05 per month, model B comes out ahead.
Estimated spend for the listed models at your usage. Numbers are derived from each model's published per-million-token rates.
- Claude Opus 4$5.25
- Gemini 2.5 Flash$0.022
Benchmarks compared
Only sourced numbers. Where a benchmark is missing for one model we show the available value rather than fabricating the other.
- HumanEval95.0
- SWE-bench Verified72.5
Claude Opus 4 fits when…
- Set the SWE-bench bar at launch
- Excellent for writing and code
- Strong long-context handling
Gemini 2.5 Flash fits when…
- Cheap and fast
- Long context
- Solid vision
- Cost-sensitive workloads, 250.0× cheaper than Claude Opus 4 on output tokens.
- Long-context tasks, handles 1.0M tokens vs 200K for Claude Opus 4.
Consider Claude Opus 4.7
Anthropic's mid-2026 flagship, ahead on SWE-bench, agent reliability, and writing quality.
Frequently asked
Is Claude Opus 4 or Gemini 2.5 Flash cheaper?
Gemini 2.5 Flash is cheaper at $0.30 / 1M tokens per million output tokens, vs $75.00 / 1M tokens for Claude Opus 4.Which has the larger context window?
Gemini 2.5 Flash accepts 1.0M tokens vs 200K for Claude Opus 4.Is Claude Opus 4 or Gemini 2.5 Flash better for coding?
Both Claude Opus 4 and Gemini 2.5 Flash are competitive on coding benchmarks. See each model's individual spec page for HumanEval and SWE-bench scores where published. For an opinionated pick, consult our Best LLM for Coding ranking.Are either of these models open source?
Neither model ships open weights, both are accessible only via their respective providers' APIs.When were Claude Opus 4 and Gemini 2.5 Flash released?
Claude Opus 4 was released by Anthropic on 2025-05-22. Gemini 2.5 Flash was released by Google on 2025-04-09.
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