Benchmark guideJuly 2026 analysis

The best coding model changes when the benchmark changes.

SWE-bench, Terminal-Bench, LiveCodeBench, and SciCode do not disagree because one is broken. They disagree because writing a function, fixing a repository, and operating a terminal are different jobs.

By Dylan Bristot14 min read

Use LiveCodeBench for code generation, SWE-bench for repository repair, Terminal-Bench for tool-using agents, and SciCode for scientific programming. If you are choosing a production coding assistant, use at least one repository benchmark, one terminal or agent benchmark, and a private evaluation from your own code.

A coding benchmark is a compressed description of a job. When people ask “which model is best at coding?”, they often combine autocomplete, algorithmic problem solving, code review, debugging, repository search, terminal use, test repair, architecture, and frontend taste into one word. No single public benchmark covers that surface.

What each coding benchmark actually measures

SWE-bench Verified

Job
Fix a real GitHub issue
Unit
Repository-level patch
Best signal
Software-engineering agents
Blind spot
Scores depend heavily on the agent, tools, retrieval, retries, and harness version.

Terminal-Bench 2.1

Job
Complete work in a terminal
Unit
Long-horizon environment task
Best signal
Tool use and recovery
Blind spot
Not a pure code-generation test; operational reasoning and scaffold quality matter.

LiveCodeBench

Job
Solve fresh programming problems
Unit
Generated solution
Best signal
Code reasoning with lower contamination risk
Blind spot
Does not reproduce repository navigation, code review, or multi-file agent work.

SciCode

Job
Implement scientific problems
Unit
Research-oriented code task
Best signal
Scientific programming
Blind spot
Specialized domain; weaker proxy for web development or routine product engineering.

HumanEval

Job
Complete a Python function
Unit
Small isolated function
Best signal
Basic code generation
Blind spot
Older, narrow, and increasingly saturated; poor proxy for modern coding agents.

Coding Index

Job
Aggregate several coding signals
Unit
Composite score
Best signal
Fast cross-model orientation
Blind spot
The weighting is a judgment. A composite can hide the exact failure mode you care about.

HumanEval still appears in many comparison articles because it is simple and familiar. It is now more useful as a historical baseline than a selection benchmark. Modern frontier models can saturate narrow function-completion tests while still failing to navigate an unfamiliar repository or recover from a broken test run.

One dataset, four different ranking questions

The tables below use the same model dataset but sort it by four different metrics. If the first-place model changes, the benchmark is not necessarily contradicting itself. The question changed.

Composite coding capability

Coding Index leaders

  1. 1
    GPT-5.6 Sol (xhigh)OpenAI · Proprietary
    78.3
  2. 2
    GPT-5.6 Terra (max)OpenAI · Proprietary
    76.7
  3. 376.5
  4. 4
    GPT-5.5 (xhigh)OpenAI · Proprietary
    74.9
  5. 574.3

Terminal agent work

Terminal-Bench 2.1 leaders

    Fresh code generation

    LiveCodeBench leaders

    1. 1
      Gemini 3 Pro Preview (high)Google · Proprietary
      92%
    2. 291%
    3. 3
      DeepSeek V3.2 SpecialeDeepSeek · Open
      90%
    4. 4
      GPT-5.2 (xhigh)OpenAI · Proprietary
      89%
    5. 589%

    Scientific programming

    SciCode leaders

    1. 160%
    2. 2
      Gemini 3.1 Pro PreviewGoogle · Proprietary
      59%
    3. 3
      Muse Spark 1.1 (xhigh)Meta · Proprietary
      58%
    4. 4
      GPT-5.6 Sol (high)OpenAI · Proprietary
      57%
    5. 5
      GPT-5.4 (xhigh)OpenAI · Proprietary
      57%

    A composite Coding Index is an efficient shortlist. It should not be the final decision. If your product is a terminal agent, a two-point composite advantage can matter less than a ten-point Terminal-Bench difference. If your users mostly ask for small Python functions, the reverse may be true.

    SWE-bench scores models and systems unless you control the harness

    SWE-bench Verified contains 500 human-validated, solvable GitHub issues. That makes it far more realistic than isolated code generation. It also makes the evaluation a system test: an agent must inspect a repository, decide what to open, create a patch, and often interpret tests.

    The official leaderboard therefore separates the full system leaderboard from a bash-only language-model view using mini-SWE-agent. Even the bash-only view tracks harness releases because tool-calling and prompt changes affect comparability. Compare models only under the same agent and release. Compare products on the full leaderboard only when the product—not the base model—is what you are buying. See the official SWE-bench Verified notes.

    The comparison rule

    Same model, different agent

    Measures scaffolding

    Different model, same agent

    Measures model contribution

    Different model and agent

    Measures complete product systems

    Build a coding scorecard around failure, not prestige

    The right scorecard starts with what an incorrect answer costs. A failed autocomplete is cheap. A plausible patch merged into a production repository is not. Weight your evaluation accordingly.

    Repository task success30%Issues from your own repositories, scored by tests and review.
    Terminal / tool reliability20%Command choice, recovery, and state over multiple steps.
    Review quality15%Find real defects without inventing noisy ones.
    Latency to accepted result15%Wall-clock time including retries, not tokens per second alone.
    Cost per accepted result10%Total model and tool cost divided by accepted outcomes.
    Security and policy fit10%Data handling, licenses, logging, and permission boundaries.

    The weights above are a starting hypothesis, not a universal formula. Change them for your workflow, preregister the acceptance rule, and keep the failed outputs. The failure clusters usually teach more than the average score.

    Methodology and sources

    • Live leader tables use Artificial Analysis metrics exposed through the WhatLLM data layer.
    • Benchmark descriptions use official benchmark documentation where available.
    • SWE-bench’s 500-task count and harness caveats come from its official Verified documentation.
    • Scores with missing coverage are excluded rather than imputed.
    • Model variants are deduplicated by base name within each top-five table.

    For the current multi-benchmark ranking, continue to Best LLM for Coding.

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