Benchmark Almanac

SWE-rebench

Claude Fable 5 64.5% leads since Jun 2026 Only in system cards

Agents fix fresh GitHub issues that an automated pipeline mines each month. Tests decide whether the issue is resolved.

Scores depend on the monthly task window, so results from different months are not directly comparable.

In the authors’ words

LLM-based agents have shown promising capabilities in a growing range of software engineering (SWE) tasks. However, advancing this field faces two critical challenges. First, high-quality training data is scarce, especially data that reflects real-world SWE scenarios, where agents must interact with development environments, execute code and adapt behavior based on the outcomes of their actions. Existing datasets are either limited to one-shot code generation or comprise small, manually curated collections of interactive tasks, lacking both scale and diversity. Second, the lack of fresh interactive SWE tasks affects evaluation of rapidly improving models, as static benchmarks quickly become outdated due to contamination issues. To address these limitations, we introduce a novel, automated, and scalable pipeline to continuously extract real-world interactive SWE tasks from diverse GitHub repositories. Using this pipeline, we construct SWE-rebench, a public dataset comprising over 21,000 interactive Python-based SWE tasks, suitable for reinforcement learning of SWE agents at scale. Additionally, we use continuous supply of fresh tasks collected using SWE-rebench methodology to build a contamination-free benchmark for agentic software engineering. We compare results of various LLMs on this benchmark to results on SWE-bench Verified and show that performance of some language models might be inflated due to contamination issues.

Abstract of SWE-rebench: An Automated Pipeline for Task Collection and Decontaminated Evaluation of Software Engineering Agents (arXiv:2505.20411, CC0)
Made by Nebius Released May 2025 Fixing real repositories All tasks public Last in a system card Feb 2026 Last model added Jul 2026 Scores refreshed 2 Nov 2026
Level
Expert Specialists with years of training, often over hours of work
Scored
Checked automatically A program checks the result against an answer key, unit tests or the expected final state.
Answers
Code A program or patch run against tests.
13
Models scored on its own leaderboard
1
System card reports it, from 1 lab

Claude Fable 5 leads with 64.5% among models released by Jul 2026

Best score per model from the benchmark's own leaderboard, read on 2 Nov 2026. Where a model ran with several settings or harnesses, we keep its best. Every run is in the next chart.

The newest model with a score here came out in Jul 2026, and nobody has tested a newer one. Among the 20 highest-ranked models on the capability index, these have no score yet:

  1. 1 Claude Fable 5 high 64.5%
  2. 2 Grok 4.5 high 63.8%
  3. 3 Claude Opus 5 high 63.4%
  4. 4 GLM-5.2 high 62.9%
  5. 5 GPT-5.6 Sol medium 62.3%
  6. 6 Claude Sonnet 5 high 56.8%
  7. 7 MiniMax-M3 47.2%
  8. 8 MiMo-V2.5-Pro 46.5%
  9. 9 GPT-5.6 Luna medium 43.6%
  10. 10 DeepSeek-V4-Pro high 40.2%
  11. 11 Qwen3.6 27B 31.2%
  12. 12 Qwen 3.6 35B-A3B 24.7%
  13. 13 Qwen3.5-35B-A3B 17.1%
#ModelScoreSettingDateSource
1 Claude Fable 5 64.5% high Jun 2026 Official leaderboard
2 Grok 4.5 63.8% high Jul 2026 Official leaderboard
3 Claude Opus 5 63.4% high Jul 2026 Official leaderboard
4 GLM-5.2 62.9% high Jun 2026 Official leaderboard
5 GPT-5.6 Sol 62.3% medium Jul 2026 Official leaderboard
6 Claude Sonnet 5 56.8% high Jun 2026 Official leaderboard
7 MiniMax-M3 47.2% Jun 2026 Official leaderboard
8 MiMo-V2.5-Pro 46.5% Apr 2026 Official leaderboard
9 GPT-5.6 Luna 43.6% medium Jul 2026 Official leaderboard
10 DeepSeek-V4-Pro 40.2% high Apr 2026 Official leaderboard
11 Qwen3.6 27B 31.2% Apr 2026 Official leaderboard
12 Qwen 3.6 35B-A3B 24.7% Apr 2026 Official leaderboard
13 Qwen3.5-35B-A3B 17.1% Feb 2026 Official leaderboard

Labs report scores for 1 model in their cards. We plot every source in the charts below.

The best score, 64.5%, costs $4.40 a task

Runs on the cost frontier score higher than any run that's cheaper. GPT-5.6 Sol at medium comes within 2.2 points of the best for $0.85 a task, 5 times cheaper. The costs are the leaderboard's own estimates, so compare them only within this benchmark.

Xiaomi Corp Anthropic Z.ai xAI OpenAI Cost frontier One model at each effort level
0% 20% 40% 60% 80% $0.10 $0.20 $0.50 $1.00 $2.00 $5.00 $10 Cost per task, log scale Claude Fable 5, high Grok 4.5, high GPT-5.6 Sol, medium MiMo-V2.5-Pro 0% 20% 40% 60% 80% $0.10 $1.00 $10 Cost per task, log scale Claude Fable 5, high MiMo-V2.5-Pro
ModelEffortHarnessScoreCost per taskOutput tokens
Claude Fable 5 high 64.5% $4.40
Grok 4.5 high 63.8% $1.47
Claude Opus 5 high 63.4% $3.47
GLM-5.2 high 62.9% $1.40
GPT-5.6 Sol medium 62.3% $0.85
Claude Sonnet 5 high 56.8% $1.43
MiniMax-M3 47.2% $0.95
MiMo-V2.5-Pro 46.5% $0.10
GPT-5.6 Luna medium 43.6% $0.11
DeepSeek-V4-Pro high 40.2% $0.15
Qwen3.6 27B 31.2% $0.62
Qwen 3.6 35B-A3B 24.7% $0.27
Qwen3.5-35B-A3B 17.1% $0.99

6 models have held number one since its release in May 2025

Lab claims count from the day the card came out, independent runs from the model’s release.

Qwen Xiaomi Corp MiniMax Anthropic
Own leaderboard Not tested since Jul 2026

Scores over time

All the scores we have, one dot each, so a model tested at several settings appears more than once.

On the benchmark’s own leaderboard Reported by the lab in its model card Best so far
0% 20% 40% 60% 80% 100% 2026 Near the ceiling (85%) Claude Fable 5 MiniMax-M3 GLM-5 0% 20% 40% 60% 80% 100% 2026 Near the ceiling (85%) Claude Fable 5 MiniMax-M3

Labs report it only in system cards

We read the headline results of 479 launch posts from 51 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.

DateDocumentScoreAs the document writes itSection
17 Feb 2026 GLM-5 technical report 42.1 SWE-rebench, January 2026, Resolved Rate (Table 9). Pass@5 50.0 Capabilities

More in Coding

All 243 in Coding
  • SWE-bench Verified In use 500 human-validated GitHub issues from 12 Python repos. Agent writes a patch that must pass hidden tests. Claude Opus 4.7 83.5%
  • SWE-bench Multilingual In use 300 GitHub-issue tasks across nine programming languages in SWE-bench format. Patch graded by repository tests. Claude Opus 5.5 93.9%
  • LiveCodeBench v6 In use Competitive programming problems collected after model cutoffs from LeetCode, AtCoder, Codeforces. Scored pass@1 on hidden tests. DeepSeek-V4-Pro 93.5%
  • DeepSWE In use 113 original long-horizon engineering tasks across 91 repos and five languages, written from scratch. Hand-written verifiers accept alternative solutions. GPT-6 Astra 74.1%
  • SciCode In use Scientist-curated research coding problems split into subproblems across natural sciences. Code checked against test cases. Seed2.1 Pro 59.8%
  • Codeforces rating In use Model solves recent Codeforces contest problems. An Elo-style rating is computed from simulated contest performance. DeepSeek V4.1 Flash 3,471