Is GLM 5.3 FlashX or Grok 4.20 Reasoning cheaper?

GLM 5.3 FlashX is cheaper on output tokens ($1.25 vs $2.50 per 1M).

Which has the larger context window, GLM 5.3 FlashX or Grok 4.20 Reasoning?

Grok 4.20 Reasoning has the larger context window (2M tokens).

GLM 5.3 FlashX vs Grok 4.20 Reasoning

GLM 5.3 FlashX is cheaper on output tokens, while Grok 4.20 Reasoning offers a larger context window. Choose GLM 5.3 FlashX or Grok 4.20 Reasoning based on the trade-off between cost, context, and the benchmarks that matter for your use case.

Spec	GLM 5.3 FlashX	Grok 4.20 Reasoning
Provider	Vercel AI Gateway	Vercel AI Gateway
Input / 1M tokens	$0.37	$1.25
Output / 1M tokens	$1.25	$2.50
Context window	1M	2M
Parameters	—	—
Open weights	Yes	No
Released	Aug 2026	Mar 2026

GLM 5.3 FlashX details →Grok 4.20 Reasoning details →

FAQ

Pricing is indicative — confirm with the provider before production use. Highlighted values indicate the better figure for that row.