Model comparison
Claude Sonnet 5 vs Gemini 2.5 Pro
Anthropic against Google, compared on context, price, and verified benchmark results.
Catalog record checked September 3, 2026Individual provider fields may changeEvidence confidence: High — see receipts below
Anthropic
Claude Sonnet 5
Balanced
Gemini 2.5 Pro
Balanced
| Specification | Claude Sonnet 5 | Gemini 2.5 Pro |
|---|---|---|
| Provider | Anthropic | |
| Tier | Balanced | Balanced |
| Context window | 1M | Winner: 1.05M |
| Max output | Winner: 128K | 66K |
| Input / 1M tokens | $2 | Winner: $1.25 |
| Output / 1M tokens | $10 | $10 |
| Weights | Closed | Closed |
| Parameters | Not disclosedUnverified | Not disclosedUnverified |
| Reasoning levels | adaptive | low, medium, high |
| Modalities | text, image | text, image, video, audio, pdf |
| API model id | claude-sonnet-5 | gemini-2.5-pro |
| Released | June 30, 2026 | June 17, 2025 |
| Artificial Analysis Intelligence Index (2026-08-14) | Winner: 55 | 47 |
| Terminal-Bench 2.1 (2026-06-30) | 80.4 | Not verifiedUnverified |
| Humanity's Last Exam (2026-06-30) | 57.4 | Not verifiedUnverified |
| SWE-bench Verified (2026-09-01) | 79.6 | Not verifiedUnverified |
| LiveBench (2026-09-05) | 76 | Not verifiedUnverified |
Prices are USD per million tokens at standard rates, excluding batch and caching discounts. Bold indicates the better figure where one is objectively better. Values we could not confirm from the provider are shown as “Not verified” rather than estimated.
Benchmark receipts
- 2026-09-05: LiveBench official leaderboard (benchmark-owned), xhigh effortContamination-resistant general capability across reasoning, coding, math, data analysis, and language, with monthly question refreshes. Comparability: comparable with caveat — Rolling question set: observations months apart measure different question mixes. Record the measurement date and compare within ~1 month windows.
- 2026-09-01: vals.ai SWE-bench Verified leaderboard (independent, mini-swe-agent bash-only); not published by Anthropic; a 72.7 CosmicJS claim is unverifiedReal GitHub issue resolution: does the model's patch pass the hidden tests. Comparability: comparable with caveat — Post-audit vendor claims and pre-audit scores sit on different task trust levels; scaffolding (agent harness, compute budget) also dominates results. Never aggregate across scaffolds.
- 2026-08-14: Artificial AnalysisComposite index blending reasoning, knowledge, and coding evals into one 0–100 score. Comparability: directly comparable — AA occasionally rebaselines the index scale between snapshots — a score captured on one date is only comparable to same-snapshot scores (check measuredAt).
- 2026-06-30: Anthropic announcement (vendor, with tools)Frontier-knowledge ceiling: extremely hard multi-domain questions written to be near-impossible without deep expertise. Comparability: comparable with caveat — Subset/tool configurations (text-only vs with-tools) differ between vendors and materially change scores; must match configuration to compare.
- 2026-06-30: Anthropic announcement table (vendor, default effort; via Vellum transcription)Agentic terminal work: multi-step tasks executed in a sandboxed shell environment. Comparability: comparable with caveat — Scores across Terminal-Bench major versions (v1 vs v2) are NOT comparable; harness configuration (container, time limits) also shifts results.
Pricing tiers: Claude Sonnet 5: Standard $2/$10 per MTok; cache reads 10% of base input. Knowledge cutoff Jan 2026. · Gemini 2.5 Pro: $1.25/$10 per MTok (≤200K); $2.50/$15 (>200K). Legacy but still widely listed.
Claude Sonnet 5
Claude Sonnet 5 is Anthropic's best speed/intelligence balance for high-volume agentic work at $2/$10.
Best for
- Everyday generation
- High-volume agents
- Cost-sensitive work
Watch out
A step below Opus 5 on the hardest tasks; pick Opus when quality is paramount.
Gemini 2.5 Pro
Gemini 2.5 Pro is Google's previous-generation Pro with a 1.05M-token context and strong multimodal support.
Best for
- Long documents
- Multimodal input
- Google Workspace integration
Watch out
A generation behind Gemini 3.x; verify on your workload.
When the cheaper one wins
Both charge $10 per million output tokens at standard rates, so output price is not the split. Prefer the row whose “best for” line matches the job, then confirm the live vendor rate.
Run the model pickerEvidence confidence: High
How strong and complete the evidence behind this comparison is — not a prediction of which model is better.
- Pricing verified on both sides — Input and output rates are verified for both models.
- 4/5 core specs verified on both sides — Not published for at least one side: parameter count.
- 1 shared named benchmark with differing scores — Measured on: Artificial Analysis Intelligence Index.
- Verified within the last 90 days — Newest catalog check was 8 days ago.
- Both models carry source citations — Each side has at least two catalog sources on record.
Source receipts
Each catalog figure was checked against the provider or an independent second source on the date shown.
- Claude Sonnet 5: Anthropic — Claude Sonnet 5 (accessed 2026-08-29)
- Claude Sonnet 5: Anthropic news — Claude Sonnet 5 (accessed 2026-08-29)
- Gemini 2.5 Pro: Google — Gemini 2.5 Pro GA (accessed 2026-08-29)
- Gemini 2.5 Pro: Google AI pricing (accessed 2026-08-29)
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Diving deeper on one model? Claude Sonnet 5 · Gemini 2.5 Pro
Common questions
Claude Sonnet 5 vs Gemini 2.5 Pro
Answered from the verified figures on this page rather than general guidance.
Is Claude Sonnet 5 or Gemini 2.5 Pro cheaper for input?
Gemini 2.5 Pro is cheaper at $1.25 per million input tokens, against $2 for Claude Sonnet 5 — roughly 1.6× the price. Output tokens usually dominate a real bill, so weigh the output rate more heavily than the input rate. These are base rates; Claude Sonnet 5 has tiered pricing: Standard $2/$10 per MTok; cache reads 10% of base input. Knowledge cutoff Jan 2026. Gemini 2.5 Pro has tiered pricing: $1.25/$10 per MTok (≤200K); $2.50/$15 (>200K). Legacy but still widely listed.
Is Claude Sonnet 5 or Gemini 2.5 Pro cheaper for output?
Both cost $10 per million output tokens at standard rates, so output price is not a deciding factor between them.
Which has the larger context window, Claude Sonnet 5 or Gemini 2.5 Pro?
Gemini 2.5 Pro accepts 1.05M tokens against 1M for Claude Sonnet 5. This only matters if you routinely send very long documents or large codebases.
Do Claude Sonnet 5 and Gemini 2.5 Pro support the same reasoning levels?
Claude Sonnet 5 exposes adaptive, while Gemini 2.5 Pro exposes low, medium, high.
Should I use Claude Sonnet 5 or Gemini 2.5 Pro?
Both sit in the balanced tier, so the choice usually comes down to price and context rather than capability. Claude Sonnet 5 suits everyday generation; Gemini 2.5 Pro suits long documents.
Next step
Choosing between them
The verified figures that separate this pair, computed from the catalog rather than restated boilerplate.
- Input price: Gemini 2.5 Pro costs $1.25 per 1M tokens versus $2 for Claude Sonnet 5 — a 1.6x difference at the headline tier.
- Context: Gemini 2.5 Pro takes 1.05M against 1M for Claude Sonnet 5 — only decisive if your prompts approach the smaller window.
- Measured capability: Claude Sonnet 5 leads Artificial Analysis Intelligence Index 55 to 47 (measured 2026-08-14).
Choosing a harness rather than a model — Cursor, Copilot, Claude Code, Windsurf, or Lovable? Compare agentic harnesses · Latest releases.