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Z.ai's open-weight family, behind the cheap coding subscriptions.

GLM is the model family from Z.ai, and the reason its coding plan turns up in every "cheaper than Claude Code" thread — the weights are published, plenty of providers serve them, and the Flash models are some of the cheapest usable coding models anywhere. The 5.3 line runs to a million tokens of context, with Flash variants that also read images and video. Z.ai's own chat app is listed separately under Chats.

At a glance — GLM 5.3 Prime

Cost
$2.80 in · $8.80 out per 1M tokensMid-range
Memory
1M tokens — about 1,500 pages
Reads
Text
Can do
  • Use tools (agents)
  • Structured output
  • Thinking mode
Reliability
99.38% uptime, last 24h
Released
Sep 23, 2026
Advanced details
API model ID
z-ai/glm-5.3-prime
Max output
131K tokens
Cached input
$0.56 per 1M
Tokenizer
Other

Providers

The same model, hosted by different companies. OpenRouter picks one per request and falls back to the next if it fails.

ProviderInput /1MOutput /1MCached /1MMax outputUptime 24h
Alibaba$2.80$8.80$0.56131K99.38%

Supported parameters

  • frequency_penalty
  • include_reasoning
  • logprobs
  • max_tokens
  • presence_penalty
  • reasoning
  • reasoning_effort
  • response_format
  • seed
  • stop
  • temperature
  • tool_choice
  • tools
  • top_k
  • top_logprobs
  • top_p

Live from OpenRouter, refreshed hourly.

Key info

Pricing
Open source
Category
Models
Best for
Intermediate
Made by
Z.ai
Weights
Open
Good for
Coding on a budget

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  • The open-weight family everyone else gets benchmarked against.

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  • Google's open models — Gemini's research, small enough to self-host.

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