Benchmark Almanac

NaturalCodeBench

GPT-4 (snapshot unspecified) 52.8% tops its leaderboard Claude 3 Opus 48.3% leads the models we track
Seed-Coder-8B-Instruct 49.6% leads since June 2025
Dropped

Models solve 402 Python and Java problems taken from real user queries to online coding services in 6 domains. Semi-automatically built tests check each solution.

Prompts come in Chinese and English versions. Labs report a total over both.

Released
May 2024
Kind
Function-level problems
Level
University
Scored
Checked automatically
Answers
Code
Strongest model tested
Claude 3 Opus #172 on the capability index
Last in a launch post
July 2025, dropped before it saturated
Last model added
August 2025
Scores refreshed
November 12th, 2026

In the authors’ words

Large language models (LLMs) have manifested strong ability to generate codes for productive activities. However, current benchmarks for code synthesis, such as HumanEval, MBPP, and DS-1000, are predominantly oriented towards introductory tasks on algorithm and data science, insufficiently satisfying challenging requirements prevalent in real-world coding. To fill this gap, we propose NaturalCodeBench (NCB), a challenging code benchmark designed to mirror the complexity and variety of scenarios in real coding tasks. NCB comprises 402 high-quality problems in Python and Java, meticulously selected from natural user queries from online coding services, covering 6 different domains. Noting the extraordinary difficulty in creating testing cases for real-world queries, we also introduce a semi-automated pipeline to enhance the efficiency of test case construction. Comparing with manual solutions, it achieves an efficiency increase of more than 4 times. Our systematic experiments on 39 LLMs find that performance gaps on NCB between models with close HumanEval scores could still be significant, indicating a lack of focus on practical code synthesis scenarios or over-specified optimization on HumanEval. On the other hand, even the best-performing GPT-4 is still far from satisfying on NCB. The evaluation toolkit and development set are available at https://github.com/THUDM/NaturalCodeBench.

Abstract of NaturalCodeBench: Examining Coding Performance Mismatch on HumanEval and Natural User Prompts (arXiv:2405.04520, CC0)
39
Entries on its own leaderboard, 5 models we track
1
Launch post lists it, from 1 lab
2
System cards report it, from 1 lab

GPT-4 (snapshot unspecified) tops the leaderboard with 52.8%

Best score per entry from the benchmark's own leaderboard, read on November 12th, 2026. Where a model ran with several settings or harnesses, we keep its best. Names in gray aren't in our model list: fine-tunes, agent systems, products and older models. They don't count toward leaders. The best model we track is Claude 3 Opus, at 48.3%.

Seed-Coder-8B-Instruct leads with 49.6%, claims included

Best score per model from every source, including labs’ own numbers and claims Epoch AI collected from reports and papers. Labs pick their own settings, so a claim can beat an independent run of the same model.

The newest model with a score here came out in April 2024, and nobody has tested a newer one. Among the 20 highest-ranked models on the capability index, these have no score yet:

  1. 1 GPT-4 (snapshot unspecified) 52.8%
  2. 2 GPT-4-Turbo-0125 52.5%
  3. 3 GPT-4-Turbo-1106 51.5%
  4. 4 Claude 3 Opus 48.3%
  5. 5 ChatGLM-4 43.9%
  6. 6 Deepseek-Coder-Instruct 33B 43%
  7. 7 Gemini-1.5-Pro (snapshot unspecified) 42.3%
  8. 8 GPT-3.5-Turbo (snapshot unspecified) 40.7%
  9. 9 Claude 3 Sonnet 38.9%
  10. 10 Llama-3-Instruct 70B 37.1%
  11. 11 Claude 3 Haiku 36.2%
  12. 12 Deepseek-Coder-Instruct 6.7B 35.1%
  13. 13 Claude 2.1 34.4%
  14. 14 Deepseek-Chat 67B 33.2%
  15. 15 Codellama-Instruct 70B 32.6%
  16. 16 Phind-Codellama 34B 32.3%
  17. 17 Qwen1.5-110B 32.2%
  18. 18 CodeGeeX3 31.9%
  19. 19 Qwen-Chat 72B 27.9%
  20. 20 WizardCoder 34B 24.8%
  21. 21 Llama-3-Instruct 8B 24.7%
  22. 22 Deepseek-Coder-Instruct 1.3B 23.9%
  23. 23 WizardCoder 15B 22.7%
  24. 24 Codellama-Instruct 34B 21.8%
  25. 25 Codellama-Instruct 13B 20.8%
  26. 26 Codellama-Instruct 7B 18.4%
  27. 27 StarCoder 15.5B 13.2%
  28. 28 Qwen-Chat 7B 13%
  29. 29 Mistral-Instruct 7B 12%
  30. 30 Deepseek-Chat 7B 10.9%
  31. 31 CodeGen2 16B 6.90%
  32. 32 CodeGen2 7B 5.00%
  33. 33 Phi 2.7B 4.20%
  34. 34 CodeGen 16B 3.90%
  35. 35 CodeGen 2B 1.50%
  36. 36 CodeGen 6B 1.50%
  37. 37 Phi 1.3B 1.20%
  38. 38 CodeGen2 3.7B 0.80%
  39. 39 CodeGen2 1B 0%

Source: Official NaturalCodeBench leaderboard

#EntryScoreSettingDateSource
1 GPT-4 (snapshot unspecified) 52.8% Official leaderboard
2 GPT-4-Turbo-0125 52.5% Official leaderboard
3 GPT-4-Turbo-1106 51.5% Official leaderboard
4 Claude 3 Opus 48.3% Feb 2024 Official leaderboard
5 ChatGLM-4 43.9% Official leaderboard
6 Deepseek-Coder-Instruct 33B 43% Official leaderboard
7 Gemini-1.5-Pro (snapshot unspecified) 42.3% Official leaderboard
8 GPT-3.5-Turbo (snapshot unspecified) 40.7% Official leaderboard
9 Claude 3 Sonnet 38.9% Feb 2024 Official leaderboard
10 Llama-3-Instruct 70B 37.1% Official leaderboard
11 Claude 3 Haiku 36.2% Mar 2024 Official leaderboard
12 Deepseek-Coder-Instruct 6.7B 35.1% Official leaderboard
13 Claude 2.1 34.4% Nov 2023 Official leaderboard
14 Deepseek-Chat 67B 33.2% Official leaderboard
15 Codellama-Instruct 70B 32.6% Official leaderboard
16 Phind-Codellama 34B 32.3% Official leaderboard
17 Qwen1.5-110B 32.2% Apr 2024 Official leaderboard
18 CodeGeeX3 31.9% Official leaderboard
19 Qwen-Chat 72B 27.9% Official leaderboard
20 WizardCoder 34B 24.8% Official leaderboard
21 Llama-3-Instruct 8B 24.7% Official leaderboard
22 Deepseek-Coder-Instruct 1.3B 23.9% Official leaderboard
23 WizardCoder 15B 22.7% Official leaderboard
24 Codellama-Instruct 34B 21.8% Official leaderboard
25 Codellama-Instruct 13B 20.8% Official leaderboard
26 Codellama-Instruct 7B 18.4% Official leaderboard
27 StarCoder 15.5B 13.2% Official leaderboard
28 Qwen-Chat 7B 13% Official leaderboard
29 Mistral-Instruct 7B 12% Official leaderboard
30 Deepseek-Chat 7B 10.9% Official leaderboard
31 CodeGen2 16B 6.90% Official leaderboard
32 CodeGen2 7B 5.00% Official leaderboard
33 Phi 2.7B 4.20% Official leaderboard
34 CodeGen 16B 3.90% Official leaderboard
35 CodeGen 2B 1.50% Official leaderboard
36 CodeGen 6B 1.50% Official leaderboard
37 Phi 1.3B 1.20% Official leaderboard
38 CodeGen2 3.7B 0.80% Official leaderboard
39 CodeGen2 1B 0% Official leaderboard
#ModelScoreSettingDateSource
1 Seed-Coder-8B-Instruct 49.6% Jun 2025 Lab model card
2 Claude 3 Opus 48.3% Feb 2024 Official leaderboard
3 Seed Diffusion Preview 42.2% Jul 2025 Lab model card
4 Claude 3 Sonnet 38.9% Feb 2024 Official leaderboard
5 Claude 3 Haiku 36.2% Mar 2024 Official leaderboard
6 Claude 2.1 34.4% Nov 2023 Official leaderboard
7 Qwen1.5-110B 32.2% Apr 2024 Official leaderboard

Labs report scores for 2 models in their cards. Switch the scores above to rank them together.

Number one over time 2 models have held number one with claims included since its release in May 2024

Lab claims count from the day the card came out, independent runs from the model’s release. We draw one row each for the benchmark’s own leaderboard and what labs claim in their cards.

Anthropic ByteDance Seed
Own leaderboard Not tested since May 2024
Lab claims Not tested since Aug 2025

Sources: Official NaturalCodeBench leaderboard and labs’ model cards

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% 2024 2025 Near the ceiling (85%) Seed-Coder-8B-Instruct Claude 3 Opus Claude 2.1 0% 20% 40% 60% 80% 100% 2024 2025 Near the ceiling (85%) Seed-Coder-8B-Instruct Claude 3 Opus

Sources: Official NaturalCodeBench leaderboard and labs’ model cards

No launch post has listed it since July 2025

Launch posts from every lab that has listed it, one tick per post. Tall colored ticks include it, and short gray ones leave it out.

ByteDance Seed
DateLaunch postScoreAs the post writes it
Jul 31, 2025 Seed Diffusion Preview 42.2 NaturalCodeBench Total

2 system cards report it, from 1 lab

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
Aug 4, 2025 Seed Diffusion Preview technical report 42.2 NaturalCodeBench Total, NCB (zh) 45.8, NCB (en) 38.6 (Table 3) Capabilities
Jun 4, 2025 Seed-Coder-8B-Instruct technical report 49.6 NaturalCodeBench Total (Table 9). NCB (zh) 50.7, NCB (en) 48.6 Capabilities

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