Anthropic · model passport
Anthropic: Claude Sonnet 4.5
claude-sonnet-4-5- Cloud only
- Proprietary licence
- 1,000,000 context
- Released 2025-09-29(curated)
- Overall · LMArena
- 1,455#61 of 396
- Best percentile
- 98.8BFCL v4 (function calling)
- Cohort standing
- 59.7median 52.6
What the data says
Benchmarked on 20 of 27 tracked axes. Every figure below is the model's own published result on that board.
Strongest axes
- 98.8 pct — BFCL v4 (function calling) (73.2%)
- 89.4 pct — Instruction following (1,462)
- 89.2 pct — SWE-bench Verified (live board) (74.8%)
Uneven: 73.2 percentile points between its best and worst axis — 98.8 pct on BFCL v4 (function calling) versus 25.6 pct on SimpleQA Verified.
- BFCL v4 (function calling)Dormant board98.8 pct73.2%Verify →
- Instruction following89.4 pct1,462Verify →
- SWE-bench Verified (live board)89.2 pct74.8%Verify →
- Coding87.7 pct1,512Verify →
- LiveBench87.3 pct72.3%Verify →
- Hard prompts86.9 pct1,483Verify →
- Overall84.8 pct1,455Verify →
- Factuality Arena64.5 pct1,449Verify →
- GPQA Diamond63.3 pct82.3%Verify →
- Terminal-Bench59.1 pct46.5%Verify →
- SimpleBench58.6 pct54.3%Verify →
- AIME (math)56 pct77.8%Verify →
- FrontierMath52.2 pct15.2%Verify →
- Humanity's Last Exam47.8 pct13.7%Verify →
- ARC-AGI-247.2 pct13.6%Verify →
- WebDev Arena36.7 pct1,394Verify →
- SWE-bench Verified31.3 pct71.3%Verify →
- Document Arena28.9 pct1,449Verify →
- HHEM Hallucination (Vectara)27.6 pct88.0%Verify →
- SimpleQA Verified25.6 pct30.7%Verify →
- Vision ArenaNot benchmarked
- Search ArenaNot benchmarked
- Agent ArenaNot benchmarked
- Terminal-Bench 4.0Not benchmarked
- MMLU-Pro (Artificial Analysis)Not benchmarked
- LiveCodeBench (Artificial Analysis)Not benchmarked
- IFBench (Artificial Analysis)Not benchmarked
Percentiles are the model's standing within each board's own population. Axes marked "not benchmarked" have no published result for this model — that is an absence of data, not a low score.
How to run it
Use it hosted
anthropic/claude-sonnet-4.5API parameters this endpoint supports
Example request
curl https://openrouter.ai/api/v1/chat/completions \
-H "Authorization: Bearer $OPENROUTER_API_KEY" \
-H "Content-Type: application/json" \
-d '{"model":"anthropic/claude-sonnet-4.5","messages":[{"role":"user","content":"Hello"}]}'Identifiers, limits and prices are synced from the upstream source shown above. Any field we haven't synced is left out entirely rather than guessed.
claude-sonnet-4-5-20250929 stands at 59.7 (raw mean 61.2) — measured on 20 of 27 axes.
claude-sonnet-4-5-20250929 stands at 59.7 versus a cohort median of 52.6 across 143 models released within 180 days — above the peer median.
claude-sonnet-4-5-20250929 scores at percentile 98.8 on BFCL v4 (function calling).
claude-sonnet-4-5-20250929 scores at percentile 89.4 on Instruction following.
claude-sonnet-4-5-20250929 ranks between #66 and #232 across 6 built-in weightings — best under "Conversation-first", worst under "All sources".
Every claim is a computed fact from the current board data, phrased by a low-temperature model call and rejected by a validation gate if any number is not in the source row. How the leaderboards work →