Claude Sonnet 5 vs GLM-5.2
Anthropic's Claude Sonnet 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 1.9x less on a blended workload, and it suits mit-licensed coding agents. Claude Sonnet 5 justifies its premium when you need fast claude-quality reasoning at scale.
Anthropic • Claude 5
$2.00 / $10.00
/ 1M tokens (input / output)
The workhorse Claude tier: a full million tokens of context and adaptive thinking at $2/$10, which undercuts the previous Sonnet 4.6 generation by a third on input while raising the context ceiling fivefold. The default pick for latency-sensitive products that still want Claude's writing and tool-use behaviour.
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 30% cheaper than Claude Sonnet 5 on input tokens.
Output price
GLM-5.2 is 56% cheaper than Claude Sonnet 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 Sonnet 5 | GLM-5.2 | Difference |
|---|---|---|---|
| Light — 1M in / 200K out | $4 | $2 | $2 |
| Moderate — 10M in / 2M out | $40 | $23 | $17 |
| Heavy — 100M in / 20M out | $400 | $228 | $172 |
Specification comparison
| Attribute | Claude Sonnet 5 | GLM-5.2 |
|---|---|---|
| Input (/ 1M tokens) | $2.00 | $1.40 |
| Output (/ 1M tokens) | $10.00 | $4.40 |
| Cached input | $0.20 | $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 | low | medium |
| Open weights | No | MIT |
| API model ID | claude-sonnet-5 | glm-5.2 |
| Status | stable | stable |
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 Sonnet 5 if…
- Production chat and copilots
- Long-document analysis
- Tool-heavy agents needing fast turns
- Code review and PR automation
Choose GLM-5.2 if…
- Coding agents on large repositories
- Long-horizon refactors
- Self-hosted agent stacks
- Structured output pipelines
Frequently asked
Is Claude Sonnet 5 or GLM-5.2 cheaper?
GLM-5.2 is cheaper. On a blended 3:1 input-to-output workload it costs about 1.9x less than Claude Sonnet 5.
Which has the larger context window, Claude Sonnet 5 or GLM-5.2?
Both accept up to 1M tokens, so context is not a differentiator here.
Should I use Claude Sonnet 5 or GLM-5.2?
Pick Claude Sonnet 5 for fast claude-quality reasoning at scale. 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.