Claude Fable 5 vs GLM-5.2
Anthropic's Claude Fable 5 and Z.ai's GLM-5.2 both target production language workloads, but they price and behave differently. Here is the side-by-side.
Pricing checked against provider documentation on . How we verify
The short answer
GLM-5.2 is the cheaper option — roughly 9.3x less on a blended workload, and it suits mit-licensed coding agents. Claude Fable 5 justifies its premium when you need long-horizon agentic engineering.
Anthropic • Claude 5
$10.00 / $50.00
/ 1M tokens (input / output)
Anthropic's most capable widely released model, built for agents that run for hours rather than seconds. Adaptive thinking is always on and cannot be disabled, which is part of why it tops the Artificial Analysis Intelligence Index — and why its cost per task runs roughly triple GPT-5.6 Sol's for a one-point intelligence lead.
Z.ai • GLM-5
$1.40 / $4.40
/ 1M tokens (input / output)
A 744B-parameter MoE with 40B active, MIT-licensed, and tuned for long-horizon coding work. It sits between DeepSeek and Kimi on price and is the usual challenger when a cheaper model keeps looping or missing repository conventions — enough capability to finish the task without flagship pricing.
Input price
GLM-5.2 is 86% cheaper than Claude Fable 5 on input tokens.
Output price
GLM-5.2 is 91% cheaper than Claude Fable 5 on output tokens — usually the side that dominates the bill.
Monthly cost at three workload sizes
Standard (non-batch, non-cached) rates. Reasoning models will exceed these figures because thinking tokens bill as output.
| Workload | Claude Fable 5 | GLM-5.2 | Difference |
|---|---|---|---|
| Light — 1M in / 200K out | $20 | $2 | $18 |
| Moderate — 10M in / 2M out | $200 | $23 | $177 |
| Heavy — 100M in / 20M out | $2,000 | $228 | $1,772 |
Specification comparison
| Attribute | Claude Fable 5 | GLM-5.2 |
|---|---|---|
| Input (/ 1M tokens) | $10.00 | $1.40 |
| Output (/ 1M tokens) | $50.00 | $4.40 |
| Cached input | $1.00 | $0.26 |
| Context window | 1,000,000 tokens | 1,000,000 tokens |
| Max output | 128,000 tokens | 131,072 tokens |
| Native reasoning | Yes | Yes |
| Knowledge cutoff | 2026-01 | 2026-02 |
| Relative latency | high | medium |
| Open weights | No | MIT |
| API model ID | claude-fable-5 | glm-5.2 |
| Status | stable | stable |
Claude Fable 5: 5-minute cache writes $12.50/MTok, 1-hour $20/MTok. Requires 30-day data retention, so not available under zero-data-retention terms.
GLM-5.2: Independently measured by Artificial Analysis; the vendor's own pricing page was unreachable at time of checking. Treat as approximate and confirm in the console.
Choose Claude Fable 5 if…
- Multi-hour autonomous coding runs
- Large codebase migrations
- Hard scientific workflows
- High-stakes legal and medical analysis
Choose GLM-5.2 if…
- Coding agents on large repositories
- Long-horizon refactors
- Self-hosted agent stacks
- Structured output pipelines
Frequently asked
Is Claude Fable 5 or GLM-5.2 cheaper?
GLM-5.2 is cheaper. On a blended 3:1 input-to-output workload it costs about 9.3x less than Claude Fable 5.
Which has the larger context window, Claude Fable 5 or GLM-5.2?
Both accept up to 1M tokens, so context is not a differentiator here.
Should I use Claude Fable 5 or GLM-5.2?
Pick Claude Fable 5 for long-horizon agentic engineering. Pick GLM-5.2 for mit-licensed coding agents. If cost dominates the decision, GLM-5.2 wins; if you need the capability ceiling, benchmark both on your own evals before committing.