Theo on Ox Alpha, Revealed as GLM-5.3-Flash

Theo discusses the model’s price, multimodal inputs and Chinese-chip deployment in a short first impression.

TBTheo BrowneSpeaker · Ping Labs
Channel
Theo - t3․gg
Published
Aug 28, 2026
Video
0:36
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1 min
Slides
3
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SUMMARY

In 30 seconds

Theo Browne says Ox Alpha, revealed as GLM-5.3-Flash, has become one of his most-used models. He praises its reported performance for its price, multimodal inputs and deployment on Chinese AI chips.

  1. 1Ox Alpha’s identityTheo says one of his most-used models turned out to be GLM-5.3-Flash.
  2. 2Performance and priceHe estimates performance comparable to Opus 4.8 at one tenth to one hundredth of the price; this is his assessment rather than a universal benchmark.
  3. 3Multimodality and chipsTheo highlights image, audio and video inputs and says the model runs on Chinese AI chips.

Takeaways

  1. Ox Alpha was revealed as GLM-5.3-Flash.
  2. Theo considers its performance competitive with Opus 4.8 at a much lower price, based on his experience.
  3. The model accepts image, audio and video inputs and was presented as running on Chinese AI chips.
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01

A fast, multimodal model

Theo shares his impressions of GLM-5.3-Flash, previously previewed as Ox Alpha. He discusses performance, pricing, inputs and the hardware used to run it.

A small DeepSWE comparison
SLIDE 1 / 3A small DeepSWE comparisonA post shows results on ten tasks and warns that the small subset could have substantial variance.
Terminal-Bench comparison
SLIDE 2 / 3Terminal-Bench comparisonThe video displays a benchmark chart comparing GLM-5.3-Flash with other models.

Ox Alpha has quickly become one of my most-used models, and I really like using it. The surprise is that it is a Flash model: GLM-5.3-Flash.

GLM-5.3-Flash announcement
SLIDE 3 / 3GLM-5.3-Flash announcementZ.ai identifies the Ox Alpha preview and describes its multimodality and hardware.

In my experience, it behaves on par with models such as Opus 4.8 at one tenth to one hundredth of the price. That is my comparison, not a guarantee that the models perform equally on every task or at every provider’s prices.

The model can take images, audio and video. That stands out to me because I say the non-Flash GLM-5.3 could not even accept a screenshot. The final surprise: the announcement says the Ox Alpha preview ran entirely on Chinese AI chips.

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