Enterprise SLA guaranteed

Powering listed enterprises
to scale AI in production

4SAPI gives enterprises a secure, high-performance, fully configurable gateway to every major LLM — with private deployment, high-concurrency handling and fine-grained access control.

  • One API keyEvery model, one endpoint
  • Fast and stableMulti-channel failover
  • Secure and compliantPrivate deployment
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99.99%
API uptime

Multi-channel failover · automatic switchover

1.2M+
Peak RPM

Smart load balancing · no rate caps

24ms
Global average latency

CN2 GIA private line · nearest-node routing

AES-256
End-to-end encryption

Private deployment · data never leaves your domain

ISO27001
Certified compliance

Audit-grade log traceability

Full Model Coverage

Every major model behind one endpoint

OpenAI, Anthropic, Google, DeepSeek and more — synced in real time and continuously expanded, with no per-vendor integration work.

  • OpenAI GPT-5.6
  • Claude Opus 5
  • Gemini 3.6
  • DeepSeek V4
  • Grok 4.5
  • Kimi K3
  • Qwen3.7 Max
  • GLM-5.2

The 4S Architecture

4SAPI — the bedrock of your enterprise

Built around speed, stability, security and scalability — a centralized AI model management platform designed for production.

SpeedRapid access

Millisecond-level scheduling across global entry points, so responses stay imperceptible to your users.

  • Global edge nodes with nearest-node routing
  • CN2 GIA private-line acceleration

StabilityAlways on

Proprietary multi-channel failover switches automatically, so your service never drops.

  • Multi-channel failover, automatic switchover
  • 99.99% SLA uptime guarantee

SecurityCompliant by design

Log traceability and permission auditing that satisfies public-company audit requirements.

  • Audit-grade log traceability
  • Fine-grained access control

ScalabilityElastic growth

Private and hybrid cloud deployment that scales horizontally with your business.

  • Private / hybrid cloud deployment
  • Seamless horizontal scaling

Core Advantages

Core advantages

Enterprise-grade guarantees behind every AI application you ship — scroll to see each one.

01 · RELIABILITY

Always on

100% official enterprise channels with proprietary multi-channel failover — switchover is automatic and your service never drops.

  • 100% official enterprise channels
  • 1+ year of stable operation, 50,000+ customers served
  • Committed to permanent operation

Multi-channel failover · live status

API uptime99.99%

Channel status

  • Primary · direct officialHealthy
  • Backup A · auto failoverHealthy
  • Backup B · smart fallbackStandby

Failover in under 0.2s · 1+ year stable · 50,000+ customers

02 · PERFORMANCE

Peak performance

Direct CN2 GIA private lines, millisecond latency, smart load balancing and high concurrency with no rate caps.

  • CN2 routing, millisecond latency
  • Smart load balancing
  • High concurrency, no rate caps

Global acceleration · measured latency

Global average latency24ms
CN2 GIA private line · smart load balancing▲ Stable

Node latency

  • East China18ms
  • South China23ms
  • Overseas41ms

High concurrency · no rate caps · 1.2M+ peak RPM

03 · COMPATIBILITY

Open and compatible

Fully compatible with the OpenAI interface protocol — change one line and every major model is ready to call.

  • OpenAI protocol compatible
  • Supports GPT, Claude, Gemini and more

OpenAI compatible · one-line switch

from openai import OpenAIclient = OpenAI(  base_url="https://4sapi.com/v1",  api_key="sk-****")

Models supported

  • GPT-5.6
  • Claude Opus 5
  • Gemini 3.6
  • DeepSeek V4
  • Grok 4.5
  • Qwen3.7 Max

No code changes · fully compatible with the OpenAI SDK and protocol

04 · BILLING

Transparent billing

Pay for what you use, inspect usage in real time, no prepaid-card risk, and company-to-company invoicing is supported.

  • Pay as you go, no prepaid-card risk
  • Company-to-company invoicing

Metered billing · usage detail

ModelUsageCost
gpt-51.2M¥ 24.0
claude-opus-4-6840K¥ 42.0
Total¥ 66.0
  • No prepaid-card risk
  • Company invoicing

Pay for what you use · credit never expires · usage visible in real time

05 · SERVICE

Round-the-clock service

24/7 self-service top-ups credited instantly, with a professional engineering team on call whenever you need them.

  • 24/7 self-service top-ups, credited instantly
  • Engineering team responds in real time

Always-on service · in safe hands

Always-on service, in safe hands

24/7 self-service top-ups and a professional engineering team responding in real time

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A professional team on call · every integration handled with care

Solutions

Different scales, one set of capabilities

From solo developers to listed enterprises, 4SAPI serves every integration, reliability and compliance need through a single gateway.

FOR DEVELOPERS · developers & teams

Integrate in minutes, call every model with one key

Skip the per-vendor integrations. One fully OpenAI-compatible endpoint calls GPT, Claude, Gemini and the rest, so your time goes into the product.

  • OpenAI SDK compatible, zero rework
  • One API key for every model
  • Pay as you go, credit never expires
  • Full docs and samples, live the same day
See the quickstart

QUICKSTART · three lines

from openai import OpenAIclient = OpenAI(  base_url="https://4sapi.com/v1",  api_key="sk-4s-****")client.chat.completions.create(model="gpt-5.6", ...)
  • GPT-5.6
  • Claude Opus 5
  • Gemini 3.6
  • DeepSeek V4

FOR ENTERPRISES · listed & large enterprises

Listed-company stability, compliance and failover

Multi-channel failover, CN2 private lines, private deployment and audit-grade logging meet the strictest public-company requirements for uptime, data compliance and governance.

  • Proprietary multi-channel failover, automatic switchover
  • Private / hybrid cloud deployment, data never leaves your domain
  • Audit-grade log traceability and access control
  • Dedicated SLA with in-region technical support
Book an enterprise demo

ENTERPRISE · stability & compliance

API uptime99.99%
  • Private deployment
  • Data stays in domain
  • ISO 27001
  • Audit logs
  • Dedicated SLA

Use Cases

One gateway across every AI scenario

Support & conversation

Multi-turn dialogue, intent recognition and knowledge Q&A answer around the clock and cut staffing costs sharply.

Content generation

Marketing copy, product descriptions and multilingual content generated in bulk, with quality and compliance intact.

Code & engineering velocity

Completion, review and generation wired into your IDE and CI pipeline for a multiplier on engineering throughput.

Docs & knowledge Q&A

RAG retrieval over company documents, policies and knowledge bases, with answers that stay traceable and auditable.

Analytics & reporting

Query data in natural language and auto-generate charts and summaries, letting business teams self-serve.

Moderation & compliance

Multi-dimensional text and image review covering grammar, content and fairness to satisfy compliance requirements.

Get Started

Connect to the world's AI, starting with 4SAPI

One API key to call every major LLM — securely, reliably and compliantly.

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