Which is cheaper, DeepSeek V4 Pro and GLM-5.3-Flash?

GLM-5.3-Flash has the lowest input price. Per 1M input tokens: DeepSeek V4 Pro from $1.74 and GLM-5.3-Flash from $0.07.

Which has the larger context window, DeepSeek V4 Pro and GLM-5.3-Flash?

GLM-5.3-Flash has the largest context window: DeepSeek V4 Pro 1,048,576 tokens and GLM-5.3-Flash 1,310,720 tokens.

Which is smarter, DeepSeek V4 Pro and GLM-5.3-Flash?

GLM-5.3-Flash scores highest on the Artificial Analysis Intelligence Index: DeepSeek V4 Pro 23.1 and GLM-5.3-Flash 27.8.

Can I switch between DeepSeek V4 Pro and GLM-5.3-Flash without changing my code?

Yes. All of them are served through FastRouter's OpenAI-compatible API, so switching is a change of the model parameter (deepseek/deepseek-v4-pro, z-ai/glm-5.3-flash).

DeepSeek V4 Pro vs GLM-5.3-Flash

Side-by-side pricing per provider, context window, benchmark scores and speed, all on one OpenAI-compatible API.

Estimate monthly cost for these models

DeepSeek V4 Pro DeepSeekdeepseek/deepseek-v4-pro

GLM-5.3-Flash Z.aiz-ai/glm-5.3-flash

Creator

DeepSeek

Z.ai

Released

Apr 24, 2026

Aug 26, 2026

Context window

1.05M

1.31M

Max output

384K

131K

Input / 1MLowest provider price

$1.74$1.74–$2.40 across 3

$0.07$0.07–$0.15 across 5

Output / 1MLowest provider price

$3.48$3.48–$4.80 across 3

$0.25$0.25–$0.50 across 5

Providers

IntelligenceArtificial Analysis index

23.1

27.8

LatencyMedian time to first token

4.9s

—

ThroughputMedian tokens per second

<1 t/s

—

Accepts

Text

Text, Image, Video

Produces

Text

Tool calling

Yes

Structured output

Yes

Reasoning

Yes

DeepSeek V4 Pro vs GLM-5.3-Flash: summary

DeepSeek V4 Pro and GLM-5.3-Flash are both available through FastRouter's OpenAI-compatible API, so switching between them is a change of model id, not a new integration.

DeepSeek V4 Pro, from DeepSeek, has a 1,048,576-token context window, costs from $1.74/1M input and $3.48/1M output tokens across 3 providers and scores 23.1 on the Artificial Analysis Intelligence Index.

GLM-5.3-Flash, from Z.ai, has a 1,310,720-token context window, costs from $0.07/1M input and $0.25/1M output tokens across 5 providers and scores 27.8 on the Artificial Analysis Intelligence Index.

GLM-5.3-Flash is the cheapest on input, 25× cheaper than the next model, GLM-5.3-Flash has the largest context window and GLM-5.3-Flash scores highest for intelligence.

Switch with one line

client = OpenAI(base_url="https://api.fastrouter.ai/api/v1", api_key="<FASTROUTER_API_KEY>") client.chat.completions.create(model="deepseek/deepseek-v4-pro", messages=[...]) # or client.chat.completions.create(model="z-ai/glm-5.3-flash", messages=[...])

Full API docs

Frequently asked questions

More comparisons

Benchmark scores sourced from ArtificialAnalysis