GLM-5.1 is available across a growing number of API providers, and the choice between them materially affects cost, latency, and what features you can actually use. The benchmark spread is real: blended pricing runs from $0.74 to $1.70 per 1M tokens across tracked providers, output speed ranges from 33 to 175 t/s, and not every provider supports JSON mode. For teams moving toward production, this guide breaks down which platform fits which workload.

Summary of the Best GLM-5.1 Providers

Provider	Best For
DeepInfra	Cost optimization and budget-conscious large-scale deployments
Fireworks	Throughput-intensive tasks requiring maximum output speed
FriendliAI	Balanced performance with dual OpenAI/Anthropic API compatibility
Z.ai (Zhipu AI)	Direct model creator access with native feature support
Wafer	Balanced high performance and low cost
SiliconFlow	Cost-sensitive workloads — note: function calling only, no JSON mode
Puter	Web developers integrating GLM-5.1 into frontend apps without backend config
MindStudio	Non-technical teams building agentic workflows without writing code
AI/ML API	Developers wanting quick integration via OpenAI-compatible codebases

Detailed Provider Reviews

DeepInfra

DeepInfra is the recommended starting point for most production GLM-5.1 deployments. It holds the lowest blended price in the market at $0.74 per 1M tokens, the lowest input price at $1.05/1M, and the lowest output price at $3.50/1M. It also ties Fireworks for the fastest time to first token at 0.94s and is the only benchmarked provider with an explicitly listed cached input rate for GLM-5.1 ($0.205/1M) — a direct cost lever for agentic workloads that resend stable prompt prefixes.

Key specs: $0.74/1M blended · $1.05/1M input · $3.50/1M output · $0.205/1M cached · 0.94s TTFT · 35 t/s output speed · 203k context · JSON mode · Function calling · Public and private endpoints

FP8 quantization enables the cost and latency profile. Private endpoint deployment is supported for teams that need dedicated capacity or data isolation. For a detailed breakdown of how DeepInfra’s economics compare across workload types, see the GLM-5.1 pricing guide.

Visit deepinfra.com/zai-org/GLM-5.1

Fireworks

Fireworks is the right choice when output throughput is the primary constraint. It leads the benchmark set at 175.2 t/s output speed, has the lowest time to first token at 0.94s (tied with DeepInfra), and posts the lowest time to first answer token at 22.58s — a meaningful figure for reasoning model deployments where thinking time adds up before any output begins.

Key specs: $0.90/1M blended · 153.8 t/s output speed · 25.60s time to first answer token · 203k context · JSON mode · Function calling · LoRA fine-tuning support · Serverless and on-demand deployments

Fireworks also supports LoRA fine-tuning for GLM-5.1, which is useful for teams adapting the model to specific domain tasks without leaving the provider’s infrastructure.

FriendliAI

FriendliAI offers a balanced performance profile — 128 t/s output speed, 1.04s TTFT, and competitive $0.90/1M blended pricing — and stands out for supporting both OpenAI and Anthropic Messages API formats. For teams migrating existing agentic frameworks or running workloads that target both API surfaces, dual compatibility reduces integration overhead.

Key specs: $0.90/1M blended · 128 t/s output speed · 1.04s TTFT · 203k context · JSON mode · Function calling · OpenAI and Anthropic Messages API compatible · Serverless and dedicated endpoints

Z.ai (Zhipu AI)

As the model’s creator, Z.ai provides direct API access with native support for GLM-5.1’s full feature set — Thinking Mode, Context Caching, and function calling — alongside Lite, Pro, and Max subscription tiers for predictable performance SLAs. For enterprises that require first-party access, contractual guarantees, or the broadest coverage of model-specific capabilities, Z.ai is the natural choice.

Key specs: Direct model creator access · Lite/Pro/Max subscription tiers · Native Thinking Mode and Context Caching · Function calling · 200k context window

Visit z.ai

Wafer

Wafer consistently ranks second across the most important metrics: $0.86/1M blended (second lowest), 160.4 t/s output speed (second fastest), and 24.74s time to first answer token (second lowest). For teams that want both strong cost discipline and strong throughput without committing to the extremes of either, Wafer is the clearest all-around alternative to DeepInfra.

Key specs: $0.86/1M blended · 160.4 t/s output speed · 1.11s TTFT · 24.74s time to first answer token · 203k context · JSON mode · Function calling

SiliconFlow

SiliconFlow offers a competitive $0.90/1M blended price but comes with two meaningful constraints: it is the only provider in the benchmark set without JSON mode support, and its TTFT is 4.47s — the highest of all tracked providers. For workloads that rely on structured output parsing or interactive latency, those limitations are disqualifying. It is best suited for batch workloads where latency tolerance is high and structured outputs are not required.

Key specs: $0.90/1M blended · 50 t/s output speed · 4.47s TTFT · 205k context · Function calling · No JSON mode

Puter

Puter provides GLM-5.1 access through Puter.js under a user-pays model, meaning developers can integrate the model into frontend web applications without managing API keys or backend infrastructure. The end user covers the inference cost directly. This architecture makes it uniquely practical for web developers shipping GLM-5.1 powered experiences without standing up a dedicated backend.

Key specs: No API keys required for frontend integration · User-pays model (free for developers) · OpenAI-compatible API · Puter.js integration · GLM-5.1 priced at $1.40/1M input · $4.40/1M output through Puter

Visit developer.puter.com

MindStudio

MindStudio is a no-code platform that wraps GLM-5.1 in a visual agent builder with 1,000+ enterprise integrations including GitHub, Jira, and Slack. It is aimed at operational and non-technical teams who want to use GLM-5.1’s agentic capabilities within their existing SaaS ecosystems without writing code or managing API infrastructure.

Key specs: Visual agent builder · 1,000+ integrations (GitHub, Jira, Slack) · Multi-model workflow orchestration · No infrastructure management required

Visit mindstudio.ai

AI/ML API

AI/ML API provides OpenAI-compatible access to GLM-5.1 with support for streaming, function calling, and GLM-5.1’s thinking and reasoning parameters. For teams with existing OpenAI SDK integrations looking to swap in GLM-5.1, the migration path is minimal — model name and base URL are the only changes required.

Key specs: OpenAI SDK compatible · Streaming support · Function calling · Thinking/reasoning parameter support

Conclusion

The right GLM-5.1 provider depends on what you are optimizing for. For most production deployments at scale, DeepInfra is the strongest starting point: lowest cost across every token metric, top-tier latency, full JSON and function calling support, and the only provider with explicit cached input pricing for agentic workloads. For maximum throughput, Fireworks leads. For a balanced alternative, Wafer is the clearest pick. For first-party access with native feature coverage, Z.ai is the right path.

Two providers worth flagging before committing: SiliconFlow’s missing JSON mode is a real operational constraint for structured output pipelines, and its 4.47s TTFT limits it to batch use cases. Puter and MindStudio serve entirely different audiences — frontend web integration and no-code workflow building respectively — and are strong in those contexts but not substitutes for direct API access.

For a detailed cost breakdown across real workload patterns, see the GLM-5.1 pricing guide. For provider performance benchmarks, see the GLM-5.1 API benchmarks.