AI Comparatives
Generative AI
8 min reading

GLM-5.2 Benchmark vs GPT-5.5, Claude Opus 4.8 and Gemini 3.1 Pro

Summarize this article with:

summary
  • GLM-5.2 is a strong open-weights coding model with a 753B-parameter MoE architecture, MIT license, and 1M-token context window.
  • GLM-5.2 performs well on coding benchmarks, scoring 62.1 on SWE-bench Pro, 81.0 on Terminal-Bench 2.1, and 74.4 on FrontierSWE.
  • GLM-5.2 is cheaper than closed frontier models, at $1.40 per 1M input tokens and $4.40 per 1M output tokens, making it useful for high-volume coding agents.
  • Claude Opus 4.8 remains stronger for the hardest agentic coding tasks, with 88.6% on SWE-bench Verified, especially when reliability matters more than cost.
  • Use GLM-5.2 when you need self-hosting, open weights, low cost, and long-context coding workflows. Use GPT-5.5, Claude, or Gemini when managed reliability, multimodal reasoning, or enterprise support matters more.

What Is GLM-5.2?

GLM-5.2 is Z.ai’s 753B-parameter open-weights MoE model for coding agents, long-context reasoning, and self-hosted AI deployments.

Z.ai, formerly Zhipu AI, released GLM-5.2 on June 13, 2026 under an MIT open-weights license. The main upgrade over GLM-5.1 is context length: 1M tokens, up from 200K tokens. That makes it relevant for repository-wide coding, long documents, and multi-step agent workflows.

GLM-5.2 supports two thinking modes:

  • High: balanced reasoning for general tasks.
  • Max: deeper reasoning, used by default for coding tasks.

The model is also natively compatible with Claude Code, Cline, Roo Code, Goose, and Ollama. You can run it through hosted APIs, test it via aggregators like Eden AI, or self-host it when infrastructure control matters.

Takeaway: GLM-5.2 is relevant if you need open-weights control, 1M-token context, and coding-agent compatibility. Next, let’s see how it performs against GPT-5.5 and Claude Opus 4.8.

GLM-5.2 Benchmark Results

The GLM-5.2 benchmark results show the largest jump in long autonomous coding tasks, not simple code completion. The main caveat is source transparency. Z.ai released no benchmark scores at launch. The numbers below come from third-party benchmark trackers, mainly BenchLM and llm-stats.

Benchmark GLM-5.2 GLM-5.1 What It Measures
SWE-bench Pro 62.1 58.4 Real software issues from GitHub-style repositories.
Terminal-Bench 2.1 81.0 62.0 Long autonomous coding tasks in a terminal environment.
FrontierSWE 74.4 N/A Long-horizon software engineering performance across complex tasks.
BenchLM Overall #3 / 124 N/A Aggregated model ranking across multiple tracked benchmark categories.

The biggest improvement is on Terminal-Bench 2.1, where GLM-5.2 gains +19 points over GLM-5.1. That matters for coding agents because terminal tasks test planning, execution, debugging, and recovery. They are closer to real developer workflows than short code snippets.

SWE-bench Pro also improves, from 58.4 to 62.1. That is a smaller gain, but still relevant for bug fixing and repository-level edits.

Takeaway: GLM-5.2 looks strongest when the task requires sustained execution, tool use, and long-context coding, not just isolated code generation.

GLM-5.2 vs GPT-5.5 Head-to-Head Benchmark

GLM-5.2 vs GPT-5.5 is close on coding benchmarks, but not close on deployment control or price. GLM-5.2 wins both listed coding scores, while GPT-5.5 keeps the advantage in closed-platform reliability.

Category GLM-5.2 GPT-5.5 Winner
SWE-bench Pro 62.1 58.6 ✓ GLM-5.2
FrontierSWE 74.4 72.6 ✓ GLM-5.2
Context Window 1M tokens 1M tokens Tie
License MIT open-weights Closed API ✓ GLM-5.2
Cost per 1M Tokens $1.40 input / $4.40 output $5.00 input / $30.00 output ✓ GLM-5.2

Where GLM-5.2 wins

  • Coding benchmarks: +3.5 points on SWE-bench Pro and +1.8 points on FrontierSWE.
  • Deployment control: MIT open weights allow self-hosting, private infrastructure, and model inspection.
  • Cost: output tokens are about 6.8x cheaper than GPT-5.5.

Where GPT-5.5 wins

  • Managed reliability: OpenAI handles inference, scaling, updates, and uptime.
  • Ecosystem maturity: GPT-5.5 fits existing OpenAI SDKs, tools, and enterprise workflows.
  • Multimodal depth: GPT-5.5 supports text and image inputs through a closed API.

Cost example: if your team processes 10M tokens/month with a 50/50 input-output split, GLM-5.2 costs about $29/month. GPT-5.5 costs about $175/month. That saves approximately $146/month.

Verdict: choose GLM-5.2 when coding performance, open weights, and cost matter more than a fully managed closed API.

GLM-5.2 vs Claude Opus 4.8 Head-to-Head Benchmark

GLM-5.2 vs Claude Opus 4.8 is a trade-off between open control and peak coding reliability. Claude leads on SWE-bench Verified. GLM-5.2 wins on cost, licensing, and self-hosting.

Category GLM-5.2 Claude Opus 4.8 Winner
SWE-bench Verified ~62% 88.6% ✓ Claude Opus 4.8
Context Window 1M tokens 1M tokens Tie
License MIT open-weights Closed API ✓ GLM-5.2
Cost per 1M Tokens ~$1.40 input / $4.40 output ~$5.00 input / $25.00 output ✓ GLM-5.2
Self-Hosting Yes No ✓ GLM-5.2

GLM-5.2 is the right pick when cost and infrastructure control matter. You can self-host it, inspect the weights, and run it inside your own environment. That matters for regulated teams, private codebases, and high-volume API workloads. It also makes sense for mid-complexity coding tasks at scale, where token cost matters more than absolute benchmark leadership.

Claude Opus 4.8 is the right pick when reliability matters more than cost. Its 88.6% SWE-bench Verified score makes it stronger for complex coding agents, ambiguous instructions, and high-stakes software tasks. You should choose Claude when broken outputs cost more than model usage. That is often true for production migrations, autonomous agents, and senior engineering workflows.

Takeaway: if you are a startup running high-volume coding automation, pick GLM-5.2. If you are an enterprise team automating critical code changes, pick Claude Opus 4.8.

GLM-5.2 vs Gemini 3.1 Pro Head-to-Head Benchmark

GLM-5.2 vs Gemini is not a clean same-workload comparison. GLM-5.2 is better framed as an open, low-cost coding model. Gemini 3.1 Pro is better framed as a closed, multimodal reasoning model.

Category GLM-5.2 Gemini 3.1 Pro Better Fit
Coding Benchmark Score 85.6 / 100 on BenchLM Coding 93.0 / 100 on BenchLM Coding Gemini on category score
Reasoning Benchmark Score Limited sourced coverage 96.4 / 100 on BenchLM Reasoning ✓ Gemini
Multimodal Capability Limited Text, image, audio, video input ✓ Gemini
License MIT open-weights Closed API ✓ GLM-5.2
Cost per 1M Tokens $1.40 input / $4.40 output $2.00 input / $12.00 output ✓ GLM-5.2

The important point is workload fit. GLM-5.2 gives you lower token cost, open weights, and self-hosting options. That matters when you run high-volume coding automation, private repo analysis, or internal agent workflows.

Gemini 3.1 Pro is stronger when the task mixes reasoning, documents, images, audio, video, and data analysis. It is the better pick for multimodal QA, spreadsheet reasoning, research synthesis, and complex business analysis.

Takeaway: use GLM-5.2 for cost-sensitive coding and self-hosted agents. Use Gemini for multimodal reasoning, data analysis, and document-heavy workflows.

Pricing Breakdown: GLM-5.2 vs GPT-5.5, Claude Opus 4.8 and Gemini 3.1 Pro

GLM-5.2 pricing is the main reason it belongs in production cost analysis. It is not just cheaper than GPT-5.5 or Claude Opus 4.8. It is cheap enough to change which workloads are viable.

Model Input per 1M Tokens Output per 1M Tokens Context Window
GLM-5.2 $1.40 $4.40 1M tokens
GPT-5.5 $5.00 $30.00 ~1M tokens
Claude Opus 4.8 $5.00 $25.00 1M tokens
Gemini 3.1 Pro $2.50 $15.00 1M tokens

For a team processing 50M tokens/month, assuming a 50/50 input-output split, monthly spend is approximately:

  • GLM-5.2: $145/month
  • GPT-5.5: $875/month
  • Claude Opus 4.8: $750/month

That means GLM-5.2 saves about $730/month vs GPT-5.5 and $605/month vs Claude Opus 4.8.

Self-hosting changes the model further. With the MIT license, GLM-5.2 has no per-token API cost when you run it yourself. But you still need to account for GPU infrastructure, serving, monitoring, and engineering time.

Takeaway: at this price, GLM-5.2 changes the math for high-volume coding agents and repository-wide code analysis.

When to Use GLM-5.2, and When Not To

GLM-5.2 belongs on the best open source coding model 2026 shortlist when cost, context length, and deployment control matter.

Use GLM-5.2 when:

  • You run high-volume coding agents and token cost directly affects margins.
  • You need self-hosting for private codebases, regulated data, or internal infrastructure rules.
  • You want MIT open-weights licensing instead of relying only on closed APIs.
  • You process long-context coding tasks on a budget, especially large repositories or technical documentation.
  • Your team already uses Cline, Claude Code, Roo Code, Goose, or Ollama and wants lower inference costs.
  • You need a model for mid-complexity coding tasks at scale, not only rare frontier tasks.

Don’t use GLM-5.2 when:

  • You need the highest score on hardest frontier reasoning tasks.
  • Your workload is mainly multimodal, with images, audio, video, or complex documents.
  • You need a managed vendor with enterprise SLA, support, and compliance guarantees.
  • Your use case is mostly non-coding, such as business analysis, research, or multimodal QA.
Scenario Recommended Model Reason
High-volume coding automation GLM-5.2 Lower cost, open weights, 1M-token context window.
Critical agentic coding tasks Claude Opus 4.8 Stronger reliability on hard software engineering tasks.
Multimodal reasoning & data analysis Gemini 3.1 Pro Stronger multimodal and reasoning benchmark coverage.

Access GLM-5.2, GPT-5.5 and Claude Opus 4.8 in one place

Eden AI lets you test GLM-5.2, GPT-5.5, Claude Opus 4.8, Gemini, and 500+ other models through one API key and one integration. That means you can compare models without rebuilding your stack each time.

For developers, the main benefit is flexibility. You can start with GLM-5.2 for cost-efficient coding tasks, then switch to another model by changing one parameter. No separate provider account. No duplicated integration work.

import requests

API_KEY = "YOUR_EDEN_AI_API_KEY"
URL = "https://api.edenai.run/v3/chat/completions"

models = [
    "zai/glm-5.2",
    "openai/gpt-5.5",
    "anthropic/claude-opus-4-8",
    "google/gemini-3.1-pro"
]

response = requests.post(
    URL,
    headers={"Authorization": f"Bearer {API_KEY}"},
    json={
        "model": models[0],
        "fallbacks": models[1:],
        "messages": [
            {"role": "user", "content": "Review this Python function for bugs."}
        ],
        "max_tokens": 500
    }
)

print(response.json()["choices"][0]["message"]["content"])

Eden AI also supports fallback routing. If GLM-5.2 is slow or unavailable, your request can automatically route to the next best model with zero code change. You can also track GLM-5.2 spend against GPT-5.5, Claude, and Gemini in one dashboard.

That keeps your model strategy practical: lower lock-in, clearer cost control, and faster benchmark testing.

FAQs: GLM-5.2 Benchmark Review

GLM-5.2 improves over GLM-5.1 mainly through a larger context window and stronger coding benchmark scores. Its context window increased from 200K tokens to 1M tokens, which helps with larger repositories and long agent workflows. On Terminal-Bench 2.1, GLM-5.2 scored 81.0, compared with 62.0 for GLM-5.1.
GLM-5.2 is best described as an open-weights model, not a fully open-source software project. Z.ai released it under an MIT open-weights license, which allows teams to self-host and inspect the model weights. That gives more deployment control than closed APIs like GPT-5.5, Claude Opus 4.8, or Gemini 3.1 Pro.
GLM-5.2 is better than GPT-5.5 on the listed software engineering benchmarks in this review. It scores 62.1 vs 58.6 on SWE-bench Pro and 74.4 vs 72.6 on FrontierSWE. GPT-5.5 still wins if you prefer a fully managed closed API and the broader OpenAI ecosystem.
Claude Opus 4.8 is stronger for the hardest repository-level code changes, based on its 88.6% SWE-bench Verified score. GLM-5.2 is more attractive when cost, self-hosting, and open weights matter more than peak reliability. For high-risk autonomous coding tasks, Claude is still the safer pick.
Yes, GLM-5.2 is natively compatible with tools like Claude Code, Cline, Roo Code, Goose, and Ollama. That makes it practical for teams already building coding-agent workflows. You can test it through hosted APIs, Eden AI, or self-hosted infrastructure.
You can test GLM-5.2 through a hosted API instead of running your own GPU infrastructure. Eden AI lets you access GLM-5.2 with one API key, alongside GPT-5.5, Claude Opus 4.8, Gemini, and other models. That is useful if you want to compare cost, latency, and output quality before committing to self-hosting.
You should consider GLM-5.2 for production coding agents if your workload is high-volume, cost-sensitive, and mostly code-focused. Its 1M-token context window and $1.40 input / $4.40 output per 1M tokens make it practical for repository analysis and agent loops. For the hardest reasoning tasks, Claude Opus 4.8 may still be a better default.
GLM-5.2 is much cheaper than GPT-5.5 and Claude Opus 4.8 on API pricing. It costs about $1.40 per 1M input tokens and $4.40 per 1M output tokens, compared with GPT-5.5 at $5.00 / $30.00 and Claude Opus 4.8 at $5.00 / $25.00. For a 50M-token monthly workload with a 50/50 input-output split, GLM-5.2 saves about $730/month vs GPT-5.5 and $605/month vs Claude Opus 4.8.

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