GLM 5.3 vs GLM 5.3 Flash: price, context window and capabilities
GLM 5.3 (z-ai/glm-5.3) is a language model from Z.ai and GLM 5.3 Flash (z-ai/glm-5.3-flash) a multimodal language model from Z.ai; both are on the OceanToken API. GLM 5.3 Flash costs less per token than GLM 5.3: $0.15 against $1.19 per 1M input tokens (87% less) and $0.50 against $3.74 per 1M output tokens (87% less). Both have a 1.05M-token context window (1,048,576 tokens). Both support tool calling, reasoning and structured outputs; only GLM 5.3 Flash also lists image input and video input.
Side by side
| Spec | GLM 5.3 −25% | GLM 5.3 Flash |
|---|---|---|
| Model | GLM 5.3z- | GLM 5.3 Flashz- |
| Publisher | Z.ai | Z.ai |
| Kind | Text | Text, vision & video |
| Context window | 1.05M tokens1,048,576 | 1.05M tokens1,048,576 |
| Input price | $1.19 / 1M tokens | $0.15 / 1M tokens |
| Output price | $3.74 / 1M tokens | $0.50 / 1M tokens |
| Cached input price | $0.26 / 1M tokens | $0.03 / 1M tokens |
| Discount (vs official, top tier) | −25% | — |
| Inputs | text | text, images and video |
| 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 Flash to spend less per token: 87% less for input and 87% less for output than GLM 5.3.
- Context size does not separate them: both hold about 1.05M tokens.
- Choose GLM 5.3 Flash if you need image input and video 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 GLM 5.3 Flash
Frequently asked questions
Which is cheaper, GLM 5.3 or GLM 5.3 Flash?
GLM 5.3 Flash. GLM 5.3 Flash costs less per token than GLM 5.3: $0.15 against $1.19 per 1M input tokens (87% less) and $0.50 against $3.74 per 1M output tokens (87% less). These are OceanToken starting prices per use; the OceanToken console always shows the current price.
Which has the larger context window, GLM 5.3 or GLM 5.3 Flash?
Neither. Both have a 1.05M-token context window (1,048,576 tokens).
Can I call both GLM 5.3 and GLM 5.3 Flash 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 z-ai/glm-5.3-flash.
Models and publishers
GLM 5.3 · GLM 5.3 Flash · All Z.ai models
More comparisons
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