GLM 5.1

by Z.ai

GLM-5.1 is Z.ai's flagship open-weight model, released in April 2026 with a sparse Mixture of Experts architecture totaling 754 billion parameters and roughly 40 billion active per token. It supports a 202,752-token context window and can generate up to 128,000 tokens per response, suiting it to long document analysis and extended code generation. Built for autonomous software engineering, GLM-5.1 reports a state-of-the-art 58.4 on SWE-Bench Pro, ahead of Claude Opus 4.6 (57.3) and GPT-5.4 (57.7), and is designed for multi-step agentic workflows where it can sustain a single task for up to eight hours across planning, execution, testing, and refinement. Rather than single-pass generation, it iteratively drafts, evaluates, and revises solutions toward production-ready code. Released under the MIT license on Hugging Face, GLM-5.1 supports function calling, thinking modes, structured output, context caching, and tool use, and can be self-hosted, fine-tuned, and deployed commercially without restrictive licensing terms. Stronger on coding and agentic tasks than on broad general reasoning, GLM-5.1 also handles multilingual content and supports streaming output during tool execution for real-time development feedback.

Key info

Input
Output
Features
Context window
203K
Max output
131K
Input price
$0.89 /1M
Output price
$3.56 /1M
  • EU residency available
  • US residency available
  • Zero data retention on pay-as-you-go
  • No training by default
  • GDPR DPA available

Available routes

GLM 5.1 runs on 6 different routes through the Opper gateway. Compare residency, ZDR, and training posture at a glance โ€” full data-handling detail per route below.

ProviderRegionZero data retentionTrainingInputOutput
MultiEnterpriseNo$0.89$3.56
USEnterpriseNo$1.05$3.50
EUEnterpriseNo$1.40$4.40
USEnterpriseNo$1.38$4.40
EUZero data retentionNo$1.40$4.40
USZero data retentionNo$1.00$3.20

Uptime and availability

GLM 5.1 runs on 4 independently monitored routes through the Opper gateway. A direct integration leaves you on one of them, the gateway serves whichever is healthy.

100%effective uptime, last 30 days
Averaged across these routes on their own, a single provider reached 99.56% over the same window.
Daily status through the gateway, which serves each request from whichever route is healthy.
4 monitored providers serve GLM 5.1.

Measured over the last 30 days from each provider's official status feed via StatusGator. Refreshed hourly. 2 further routes for this model are not on the board yet and are not counted above. See uptime for every provider Opper monitors.

Data handling per route

Each route hosting GLM 5.1 has its own privacy posture, residency, and GDPR terms. Postures are maintained by Opper with a last-verification timestamp.

Alibaba Cloud โ€” Germany๐Ÿ‡ฉ๐Ÿ‡ช

Zero data retention is available via Opper Enterprise contract. No training on customer data. GLOBAL; SCCs; DPA available.

Zero data retention
Available via Opper Enterprise contract.
Training
No training on customer data.
Logging
Abuse monitoring
Third-party access
None disclosed
GDPR DPA
DPA available
Transfer mechanism
SCCs

DeepInfra โ€” United States๐Ÿ‡บ๐Ÿ‡ธ

Zero data retention is available via Opper Enterprise contract. No training on customer data. US; unknown.

Zero data retention
Available via Opper Enterprise contract.
Training
No training on customer data.
Logging
Limited debug logs
Third-party access
None disclosed
GDPR DPA
No DPA
Transfer mechanism
unknown

Nebius โ€” Finland๐Ÿ‡ซ๐Ÿ‡ฎ

Zero data retention is available via Opper Enterprise contract. No training on customer data. EU; DPA available.

Zero data retention
Available via Opper Enterprise contract.
Training
No training on customer data.
Logging
Abuse monitoring
Third-party access
Provider may share with subprocessors / partners
GDPR DPA
DPA available
Transfer mechanism
Not applicable โ€” data stays in EU

Novita โ€” United States๐Ÿ‡บ๐Ÿ‡ธ

Zero data retention is available via Opper Enterprise contract. No training on customer data. US; SCCs; DPA available.

Zero data retention
Available via Opper Enterprise contract.
Training
No training on customer data.
Logging
Abuse monitoring
Third-party access
None disclosed
GDPR DPA
DPA available
Transfer mechanism
SCCs

TensorX โ€” European Union๐Ÿ‡ช๐Ÿ‡บ

Zero data retention is on by default on Pay-as-you-go โ€” no action required. No training on customer data. EEA; SCCs; DPA available.

Zero data retention
On by default on Pay-as-you-go.
Training
No training on customer data.
Logging
None
Third-party access
Provider may share with subprocessors / partners
GDPR DPA
DPA available
Transfer mechanism
SCCs

Wafer โ€” United States๐Ÿ‡บ๐Ÿ‡ธ

Zero data retention is on by default on Pay-as-you-go โ€” no action required. No training on customer data. US; unknown; DPA available.

Zero data retention
On by default on Pay-as-you-go.
Training
No training on customer data.
Logging
None
Third-party access
Provider may share with subprocessors / partners
GDPR DPA
DPA available
Transfer mechanism
unknown

Benchmarks

Independent benchmark scores โ€” composite indices for reasoning, coding, and math, plus individual eval scores where available.

Global rank#74 of 596 LLMs
TierStrong
Output speed0 tok/s
First token0.00s
Intelligence Index41.0
Coding Index55.8
Reasoning & knowledge
GPQA Diamond
87%
Humanity's Last Exam
30%
Long-context reasoning
68%
Coding
SciCode
44%
Agentic & tool use
Terminal-Bench Hard
43%
ฯ„ยฒ-Bench Telecom
98%
Math & instruction following
IFBench
76%

Get started

Call GLM 5.1 through the Opper gateway with one API key. Let your coding agent set it up, or call it directly โ€” Opper is drop-in compatible with the OpenAI, Anthropic, and Google AI SDKs.

Set it up with your agent

Copy this and paste it into a coding agent like Claude Code, Cursor or Codex and it'll wire up Opper for you.

Or call it directly

import OpenAI from "openai";
const client = new OpenAI({
apiKey: process.env.OPPER_API_KEY,
baseURL: "https://api.opper.ai/v3/compat",
});
const completion = await client.chat.completions.create({
model: "alibaba:global/glm-5.1",
messages: [{ role: "user", content: "Hello" }],
});
console.log(completion.choices[0].message.content);

Compare GLM 5.1 withโ€ฆ

Side-by-side on privacy, EU hosting, pricing, and benchmarks.

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