Head to Head

zai-org/GLM-5.1 vs deepseek-ai/DeepSeek-V4-Flash

Pricing, experience, and what the community actually says.

zai-org/GLM-5.1

Starting at

$1.40 / 1M input tokens

Refund

Pay-as-you-go model; no refunds on consumed tokens. Unused credits may expire per provider terms.

Try Free →

★ Our Pick

deepseek-ai/DeepSeek-V4-Flash

Starting at

$0.028 per 1M input tokens (cache hit)

Refund

Prepaid balance is non-refundable; pay-as-you-go consumption applies.

Try Free →

Our Take

zai-org/GLM-5.1

“Worth it for developers and enterprises needing a highly capable, commercially permissive model for software engineering and complex multi-step agents, provided latency and token costs fit the budget.”

GLM-5.1 delivers frontier-level reasoning and coding performance under an open MIT license, but its high token cost and slower inference speed make it best suited for specialized, high-value tasks rather than high-volume, low-latency applications.

deepseek-ai/DeepSeek-V4-Flash

“Yes, particularly for teams prioritizing cost-efficiency and long-context processing without sacrificing core reasoning performance.”

DeepSeek-V4-Flash delivers strong reasoning and long-context capabilities at a fraction of the cost of leading Western models, making it a highly practical choice for developers and enterprises.

Pros & Cons

zai-org/GLM-5.1

✓Strong multi-step reasoning and coding performance

✓Commercially permissive MIT license

✓Large 200k context window

✓Open-weight with transparent architecture

✓High benchmark scores (Intelligence Index: 51)

✗Higher token pricing compared to many open models

✗Slower inference speed (~44 t/s)

✗High verbosity increases output costs

✗Text-only input/output requires separate vision models

✗Heavy hardware requirements for self-hosting

deepseek-ai/DeepSeek-V4-Flash

✓Highly competitive API pricing

✓1M token context window

✓Strong reasoning and coding benchmarks

✓OpenAI-compatible API structure

✓Efficient MoE architecture

✗Some features remain in beta

✗Limited official enterprise support channels

✗Performance can vary based on region and server load

✗Requires careful prompt engineering for thinking modes

Full Breakdown

Category

zai-org/GLM-5.1

deepseek-ai/DeepSeek-V4-Flash

Overall Rating

4.2 / 5

★8.5 / 5

Starting Price

$1.40 / 1M input tokens

$0.028 per 1M input tokens (cache hit)

Learning Curve

Moderate. Requires familiarity with OpenAI-compatible SDKs, prompt engineering for reasoning modes, and token budget management due to verbosity.

Low for developers familiar with OpenAI-compatible APIs; requires understanding of thinking vs. non-thinking modes.

Best Suited For

Software engineering teams, AI agent developers, and researchers requiring strong multi-step reasoning and open-weight deployment flexibility.

Developers, AI researchers, and businesses building cost-sensitive applications, long-document analysis tools, and automated coding agents.

Support Quality

Standard developer documentation and community support via GitHub and Hugging Face. No dedicated enterprise SLA is publicly advertised for the open-weight version.

Community-driven via Discord and GitHub; official enterprise support details are limited in public documentation.

Hidden Costs

High verbosity can significantly increase output token consumption. Self-hosting requires substantial GPU infrastructure due to the 754B parameter size.

Standard API token consumption; no hidden fees, but context caching requires specific implementation.

Refund Policy

Pay-as-you-go model; no refunds on consumed tokens. Unused credits may expire per provider terms.

Prepaid balance is non-refundable; pay-as-you-go consumption applies.

Platforms

Cloud API, Self-hosted (GPU), Hugging Face, ModelScope

Web API, Cloud Inference

Features

Watermark on Free Plan

✗ No

Mobile App

✗ No

API Access

✓ Yes

zai-org/GLM-5.1 Review →Try Free →

deepseek-ai/DeepSeek-V4-Flash Review →Try Free →