DeepSeek V4.1 Flash 1017 or GLM-5.3-Flash: which to choose?

Side-by-side comparison

Criterion	DeepSeek V4.1 Flash 1017	GLM-5.3-Flash
Developer	DeepSeek	Zhipu AI (Z.ai)
Released	October 17, 2026	September 18, 2026
Capability index	90.6 / 100	71.9 / 100
Input price	$0.15	$0.30
Output price	$0.60	$1.05
Cost of a typical task	$0.004	$0.008
Context window	1,048,576 tokens	1,000,000 tokens
Maximum output	393,216 tokens	131,072 tokens
Reasoning mode	Yes	Yes
Tool calling	Yes	Yes
Accepted inputs	text, image	text, image, video, PDF
Open weights	Yes	Yes
Knowledge cutoff	May 2025	Not disclosed

Two models head to head

This comparison pits two open-weight models that you can install on your own servers against each other: DeepSeek V4.1 Flash 1017 and GLM-5.3-Flash, one from DeepSeek, the other from Zhipu AI (Z.ai). The first dates from October 17, 2026, the second from September 18, 2026.

All figures below come from public sources checked on October 22, 2026: models.dev and OpenRouter for prices and capabilities, Epoch AI for scores.

Which one is more capable?

On our capability index, DeepSeek V4.1 Flash 1017 scores 90.6 out of 100 and GLM-5.3-Flash 71.9. DeepSeek V4.1 Flash 1017 leads by 18.7 points.

On the 3 benchmarks reported for both, DeepSeek V4.1 Flash 1017 wins 3 times and GLM-5.3-Flash 0:

GPQA Diamond (PhD-level science questions): DeepSeek V4.1 Flash 1017 93.2%, GLM-5.3-Flash 90.2%
OTIS Mock AIME (competition mathematics problems): DeepSeek V4.1 Flash 1017 99.4%, GLM-5.3-Flash 93.9%
FrontierMath (very hard research-level mathematics): DeepSeek V4.1 Flash 1017 71.2%, GLM-5.3-Flash 55.8%

Pricing

DeepSeek V4.1 Flash 1017 costs $0.15 per million input tokens and $0.60 per million output tokens; GLM-5.3-Flash costs $0.30 and $1.05.

For a typical agent task (read 20,000 tokens, write 2,000), expect $0.004 with DeepSeek V4.1 Flash 1017 versus $0.008 with GLM-5.3-Flash. DeepSeek V4.1 Flash 1017 is 1.9 times cheaper, a gap that adds up quickly over 1,000 tasks: $3.87 difference.

Run the numbers with your own volumes in the agent cost calculator.

Under the hood

DeepSeek V4.1 Flash 1017 reads more in one go: 1,048,576 tokens of context (roughly 1,573 pages), versus 1,000,000 for GLM-5.3-Flash.

Reasoning mode: DeepSeek V4.1 Flash 1017 yes, GLM-5.3-Flash yes. Tool calling: DeepSeek V4.1 Flash 1017 yes, GLM-5.3-Flash yes. Image input: DeepSeek V4.1 Flash 1017 yes, GLM-5.3-Flash yes.

Both publish their weights: you can host them yourself.

In short

Our reading of the data:

Choose DeepSeek V4.1 Flash 1017 for a higher capability index and a lower cost.

This verdict relies on public figures; it does not replace a trial on your own tasks.

Frequently asked questions

DeepSeek V4.1 Flash 1017 or GLM-5.3-Flash: which is better?

On our index (Epoch AI data), DeepSeek V4.1 Flash 1017 scores 90.6 and GLM-5.3-Flash 71.9 out of 100. The best choice also depends on price and on your use case.

Which one is cheaper?

DeepSeek V4.1 Flash 1017. To read 20,000 tokens and write 2,000, expect $0.004 with DeepSeek V4.1 Flash 1017 and $0.008 with GLM-5.3-Flash (prices as of October 22, 2026).

Which one has the larger context window?

DeepSeek V4.1 Flash 1017, with 1,048,576 tokens versus 1,000,000.

Can I run DeepSeek V4.1 Flash 1017 or GLM-5.3-Flash on my own servers?

Yes, both publish their weights. Check each license before commercial use.

DeepSeek V4.1 Flash 1017 versus GLM-5.3-Flash