A side-by-side comparison of GLM-5.3 and GPT-6 Astra: input/output pricing, capabilities and available endpoints, served live from J8API. Both are reachable with the same API key.
| Item | GLM-5.3 | GPT-6 Astra |
|---|---|---|
| Input (per 1M tokens) | $0.77 | $6.5 |
| Output (per 1M tokens) | $2.42 | $32.5 |
| Cache read explicit (per 1M tokens) | $0.143 | $0.65 |
| Cache write 5m (per 1M tokens) | — | $8.125 |
| Item | GLM-5.3 | GPT-6 Astra |
|---|---|---|
| Context window | 1,048,576 | 922,000 |
| Max output | 131,072 | 128,000 |
| Item | GLM-5.3 | GPT-6 Astra |
|---|---|---|
| function_calling | Yes | Yes |
| prompt_caching | Yes | Yes |
| vision | — | Yes |
On input, GLM-5.3 is cheaper ($0.77 vs $6.5 per 1M tokens). On output, GLM-5.3 is cheaper ($2.42 vs $32.5 per 1M tokens). All prices are per million tokens in USD.
GLM-5.3 does — GLM-5.3 accepts 1,048,576 input tokens and GPT-6 Astra accepts 922,000.
both support function_calling, prompt_caching; only GPT-6 Astra supports vision.
Yes. Both are available on J8API through one API key and the same OpenAI-compatible endpoint — switching means changing the model field from "glm-5.3" to "gpt-6-astra", nothing else.
Both are available on J8API under one API key — switching between them means changing the model field and nothing else, so you can use each where it fits rather than picking one.