GLM-5.3-Flash API Pricing

$0.15/M input, $0.03/M on a cache hit and $0.50/M output. Those were always the list rates; a 50% opening discount charged half of each — $0.075, $0.015 and $0.25 — until 24:00 on September 9, 2026 (UTC+8), and Z.ai let it expire on the published date rather than extending it. Because this catalogue stored the list throughout, no figure on this page had to change when the discount lapsed.

Because a promotion that ends quietly would otherwise turn every stored figure false overnight, and because comparisons across 300 rows only hold if they are all on the same basis. Chinese vendors run these discounts constantly and often without an end date; recording the list keeps the catalogue consistent and errs toward over-estimating your bill rather than under-estimating it. September 9 is what that policy is for: the discount ended and not one number on this page had to move.

GLM-5.3 lists at $1.4/M input and $4.4/M output — 9.3x and 8.8x this model's list rate. On the agentic blend the gap is 8.9x. The Flash is also the more capable model in one respect the flagship cannot match: it is natively multimodal, where GLM-5.3 is text in and text out.

No. Z.ai documents that thinking.type only supports enabled on this model, so reasoning tokens are billed as output on every call. Budget the output side more generously than a non-reasoning model of the same price would need — the vendor recommends reasoning_effort: max and setting thinking.clear_thinking to false.

Images, video and files, natively — Z.ai calls it "the first native multimodal model in the GLM-5 series" and the visual capability is built into the coding loop rather than bolted on, so the model can look at rendered output and iterate. Text parameters match GLM-5.3, including the 1M-token context window.

Z.ai marks cached input storage as limited-time free across the whole GLM line. That is a separate charge from the token rates — a fee for holding the cache, not for reading it — and this catalogue does not model it. The $0.03/M cache-hit rate above is unaffected by it.