BenchCAD 2.1
Models reconstruct parts, assemblies, and circuit boards from drawings and images. The Core set contains 100 problems with partial credit.
Models use 60 rounds and 500,000 output tokens in the standard harness. The revised scorer makes scores incomparable with earlier versions. Core requires a Hugging Face account with access. Public samples are available.
- Made by
- BenchCAD team
- Released
- October 2026
- Kind
- CAD models
- Level
- Expert
- Scored
- Checked automatically
- Answers
- Agent task
- Tasks
- Public, plus a private test set
- Strongest model tested
- Claude Fable 5.2 #1 on the capability index
- Last in a system card
- November 2026
- Last model added
- November 2026
- Scores refreshed
- November 12th, 2026
Claude Fable 5.2 leads with 83.5%
Best score per model from the benchmark's own leaderboard, read on November 12th, 2026. Where a model ran with several settings or harnesses, we keep its best. Every run is in the next chart.
- 1 Claude Fable 5.2 max 83.5%
- 2 Claude Opus 5.5 max 65.3%
- 3 Claude Sonnet 5.5 max 60.9%
- 4 Claude Fable 5.1 max 44.4%
- 5 Claude Haiku 5.5 max 22.9%
Source: Official BenchCAD 2.1 leaderboard
| # | Model | Score | Setting | Date | Source |
|---|---|---|---|---|---|
| 1 | Claude Fable 5.2 | 83.5% | max, Claude Code | Nov 2026 | Official leaderboard |
| 2 | Claude Opus 5.5 | 65.3% | max, Claude Code | Sep 2026 | Official leaderboard |
| 3 | Claude Sonnet 5.5 | 60.9% | max, Claude Code | Sep 2026 | Official leaderboard |
| 4 | Claude Fable 5.1 | 44.4% | max, Claude Code | Sep 2026 | Official leaderboard |
| 5 | Claude Haiku 5.5 | 22.9% | max, Claude Code | Oct 2026 | Official leaderboard |
Labs report scores for 1 model in their cards. We plot every source in the charts below.
The best score, 83.5%, costs $51 a task
Runs on the cost frontier score higher than any run that's cheaper. The costs are the leaderboard's own estimates, so compare them only within this benchmark.
Source: Official BenchCAD 2.1 leaderboard
| Model | Effort | Harness | Score | Cost per task | Output tokens |
|---|---|---|---|---|---|
| Claude Fable 5.2 | max | Claude Code | 83.5% | $51 | |
| Claude Fable 5.2 | max | BenchCAD 2.1 | 75.4% | $23 | |
| Claude Fable 5.2 | xhigh | Claude Code | 74% | $23 | |
| Claude Fable 5.2 | xhigh | BenchCAD 2.1 | 70.2% | $17 | |
| Claude Opus 5.5 | max | Claude Code | 65.3% | $20 | |
| Claude Sonnet 5.5 | max | Claude Code | 60.9% | $16 | |
| Claude Fable 5.2 | high | Claude Code | 60.9% | $10 | |
| Claude Fable 5.2 | high | BenchCAD 2.1 | 59.2% | $9.00 | |
| Claude Opus 5.5 | xhigh | Claude Code | 54.5% | $9.00 | |
| Claude Opus 5.5 | max | BenchCAD 2.1 | 49% | $8.10 | |
| Claude Sonnet 5.5 | max | BenchCAD 2.1 | 46.8% | $6.10 | |
| Claude Fable 5.1 | max | Claude Code | 44.4% | $35 | |
| Claude Opus 5.5 | xhigh | BenchCAD 2.1 | 42.4% | $5.20 | |
| Claude Fable 5.1 | xhigh | Claude Code | 40.5% | $28 | |
| Claude Sonnet 5.5 | xhigh | Claude Code | 39.4% | $4.00 | |
| Claude Sonnet 5.5 | xhigh | BenchCAD 2.1 | 37% | $3.50 | |
| Claude Fable 5.1 | max | BenchCAD 2.1 | 36.3% | $20 | |
| Claude Fable 5.1 | xhigh | BenchCAD 2.1 | 34% | $17 | |
| Claude Fable 5.2 | medium | Claude Code | 32.4% | $3.00 | |
| Claude Opus 5.5 | high | Claude Code | 29.7% | $2.70 | |
| Claude Fable 5.2 | medium | BenchCAD 2.1 | 28.6% | $2.00 | |
| Claude Fable 5.2 | low | Claude Code | 26.8% | $2.00 | |
| Claude Fable 5.1 | high | Claude Code | 25.8% | $13 | |
| Claude Opus 5.5 | high | BenchCAD 2.1 | 24.3% | $2.10 | |
| Claude Haiku 5.5 | max | Claude Code | 22.9% | $3.20 | |
| Claude Fable 5.2 | low | BenchCAD 2.1 | 21.3% | $1.00 | |
| Claude Fable 5.1 | high | BenchCAD 2.1 | 20.4% | $6.90 | |
| Claude Opus 5.5 | medium | Claude Code | 19.1% | $1.20 | |
| Claude Haiku 5.5 | max | BenchCAD 2.1 | 18.6% | $1.40 | |
| Claude Haiku 5.5 | xhigh | Claude Code | 17.9% | $1.40 | |
| Claude Sonnet 5.5 | high | Claude Code | 16.5% | $0.96 | |
| Claude Sonnet 5.5 | high | BenchCAD 2.1 | 16.1% | $1.00 | |
| Claude Fable 5.1 | medium | Claude Code | 15.7% | $6.10 | |
| Claude Opus 5.5 | medium | BenchCAD 2.1 | 15.1% | $0.89 | |
| Claude Haiku 5.5 | xhigh | BenchCAD 2.1 | 14.9% | $0.47 | |
| Claude Fable 5.1 | medium | BenchCAD 2.1 | 12.1% | $3.20 | |
| Claude Fable 5.1 | low | Claude Code | 12.1% | $3.20 | |
| Claude Haiku 5.5 | high | Claude Code | 11.2% | $0.17 | |
| Claude Haiku 5.5 | high | BenchCAD 2.1 | 9.10% | $0.06 | |
| Claude Fable 5.1 | low | BenchCAD 2.1 | 8.20% | $1.50 | |
| Claude Opus 5.5 | low | BenchCAD 2.1 | 6.90% | $0.15 | |
| Claude Opus 5.5 | low | Claude Code | 6.30% | $0.17 | |
| Claude Sonnet 5.5 | medium | BenchCAD 2.1 | 6.10% | $0.11 | |
| Claude Haiku 5.5 | medium | BenchCAD 2.1 | 6.00% | $0.01 | |
| Claude Sonnet 5.5 | medium | Claude Code | 5.70% | $0.10 | |
| Claude Haiku 5.5 | medium | Claude Code | 5.50% | $0.01 | |
| Claude Sonnet 5.5 | low | BenchCAD 2.1 | 5.20% | $0.08 | |
| Claude Sonnet 5.5 | low | Claude Code | 5.00% | $0.08 | |
| Claude Haiku 5.5 | low | BenchCAD 2.1 | 4.90% | $0.008 | |
| Claude Haiku 5.5 | low | Claude Code | 4.90% | $0.006 |
2 models have held number one on the official leaderboard since its release in October 2026
Lab claims count from the day the card came out, independent runs from the model’s release.
Source: Official BenchCAD 2.1 leaderboard
Scores over time
All the scores we have, one dot each, so a model tested at several settings appears more than once.
Sources: Official BenchCAD 2.1 leaderboard and labs’ model cards
Labs report it only in system cards
We read the headline results of 522 launch posts from 52 labs, and none of them list this benchmark. Some system cards do, below.
One system card reports it
Besides launch posts, we read the system cards, model cards and technical reports labs publish with a release. They report far more, including safety and frontier-risk tests.
| Date | Document | Score | As the document writes it | Section |
|---|---|---|---|---|
| Nov 9, 2026 | Claude Fable 5.2 system card | 75.4 | BenchCAD 2.1 Core, 100 problems, no tools, adaptive thinking max effort, official scorer, five runs, up to 60 rounds and 500k output tokens. With tools 83.5%, without round or token limits. Not comparable with BenchCAD 1.0 (Section 8.13.2) | Capabilities |
One lab claim next to the leaderboard
Each score a lab reported for its own model, beside the same model's best score on the leaderboard. Gaps mostly come from different harnesses, effort levels and task subsets. Every benchmark.
| Model | Lab says | Board says | Gap |
|---|---|---|---|
| Claude Fable 5.2 | 75.4% BenchCAD 2.1 Core, 100 problems, no tools, adaptive thinking max effort, official scorer, five runs, up to 60 rounds and 500k output tokens. With tools 83.5%, without round or token limits. Not comparable with BenchCAD 1.0 (Section 8.13.2) | 83.5% Leaderboard, max, Claude Code | −8.1 pts |
Versions
We switch the top row to each new version when it comes out. Open it for one row per version. An old version stays in play while people still test it, so whoever first takes it past 85% gets credit for closing it out.
Sources: Official leaderboards and labs’ model cards
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