UltraGPT
Z.ai: GLM 5.1
GLM-5.1 delivers a major leap in coding capability, with particularly significant gains in handling long-horizon tasks. Unlike previous models built around minute-level interactions, GLM-5.1 can work independently and continuously on...
Intelligence overview
204.8K tok
Context window
128K tok
Max output
What Z.ai: GLM 5.1 can do.
Reasoning
Extended reasoning
Works through problems step by step before answering, trading latency for accuracy on harder tasks.
Development
Tool calling
Calls external functions mid-response, then continues reasoning from the result.
Structured output
Returns responses constrained to a JSON schema, ready to parse without cleanup.
Streaming
Streams tokens as they're generated instead of waiting on the full response.
Performance
Design Arena — ranked #1 across 21 categories
Pay for what you use.
Every model in UltraGPT runs behind one flat subscription — this is the underlying per-token cost the catalog tracks.
$0.966 / 1M tok
$3.04 / 1M tok
Built for serious work.
Build
Generate and refactor code, with the ability to run and verify tool calls and return structured, parseable output.
Think
Works through multi-step problems with extended reasoning before it answers.
Research
Holds up to 204.8K tokens of source material in context without losing the thread.
Automate
Chains tool calls across multi-step workflows, reasoning between each one.
Ask Z.ai: GLM 5.1 anything.
A preview of the real UltraGPT composer — the model you see here is the model you get.
Continues in the UltraGPT app — one login, every model.
How Z.ai: GLM 5.1 stacks up.
The closest models in the catalog by provider, capability and score — real entries, pulled from the same directory.
Technical details.
Specification
- Context window
- 204.8K tokens
- Max output
- 128K tokens
- Input modalities
- Text
- Output modalities
- Text
- Release date
- Apr 7, 2026
- Streaming
- Supported
- Tool calling
- Supported
- JSON mode
- Supported
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