GLM 5.3 vs Claude Fable 5.1: price, context window and capabilities
GLM 5.3 (z-ai/glm-5.3) is a language model from Z.ai and Claude Fable 5.1 (anthropic/claude-fable-5.1) a multimodal language model from Anthropic; both are on the OceanToken API. GLM 5.3 costs less per token than Claude Fable 5.1: $1.19 against $9.00 per 1M input tokens (87% less) and $3.74 against $45.00 per 1M output tokens (92% less). Claude Fable 5.1 is 10% off its official price on OceanToken, for every account. GLM 5.3 has the larger context window: 1.05M tokens (1,048,576) against 1M (1,000,000) for Claude Fable 5.1. Both support tool calling, reasoning and structured outputs; only Claude Fable 5.1 also lists image input and file input.
Side by side
| Spec | GLM 5.3 −25% | Claude Fable 5.1 −10% |
|---|---|---|
| Model | GLM 5.3z- | Claude Fable 5.1anthropic/ |
| Publisher | Z.ai | Anthropic |
| Kind | Text | Text & vision |
| Context window | 1.05M tokens1,048,576 | 1M tokens1,000,000 |
| Input price | $1.19 / 1M tokens | $9.00 / 1M tokens |
| Output price | $3.74 / 1M tokens | $45.00 / 1M tokens |
| Cached input price | $0.26 / 1M tokens | $0.25 / 1M tokens |
| Cache write price | – | $12.50 / 1M tokens |
| Web search price | – | $0.01 / search |
| Discount (vs official, top tier) | −25% | −10% |
| Inputs | text | text, images and files |
| Outputs | text | text |
| Tool calling | Yes | Yes |
| Reasoning | Yes | Yes |
| Structured outputs | Yes | Yes |
About these prices
Which should you choose?
- Choose GLM 5.3 to spend less per token: 87% less for input and 92% less for output than Claude Fable 5.1.
- Choose GLM 5.3 for the longest inputs: its context window holds 1.05M tokens against 1M for Claude Fable 5.1.
- Choose Claude Fable 5.1 if you need image input and file input: GLM 5.3 does not list them.
- Not sure? Call both with the same OceanToken API key and compare them on your own prompts; each request is billed per use from one prepaid balance.
Get API Key GLM 5.3 Claude Fable 5.1
Frequently asked questions
Which is cheaper, GLM 5.3 or Claude Fable 5.1?
GLM 5.3. GLM 5.3 costs less per token than Claude Fable 5.1: $1.19 against $9.00 per 1M input tokens (87% less) and $3.74 against $45.00 per 1M output tokens (92% less). Claude Fable 5.1 is 10% off its official price on OceanToken, for every account. The OceanToken console always shows the current price.
Which has the larger context window, GLM 5.3 or Claude Fable 5.1?
GLM 5.3. GLM 5.3 has the larger context window: 1.05M tokens (1,048,576) against 1M (1,000,000) for Claude Fable 5.1.
Can I call both GLM 5.3 and Claude Fable 5.1 with one API key?
Yes. Both are on the OceanToken API at https://api.oceantoken.ai/v1: one API key and one prepaid balance call either model. Send the model id z-ai/glm-5.3 or anthropic/claude-fable-5.1.
Models and publishers
GLM 5.3 · Claude Fable 5.1 · All Z.ai models · All Anthropic models
More comparisons
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