Verified 2026 API Rates • Prompt Caching & Batch ROI

Z.ai: GLM 5.1 vs Qwen: Qwen3.5 397B A17B

Compare real-world API costs for Z.ai: GLM 5.1 ($1.4/$4.4) vs Qwen: Qwen3.5 397B A17B ($0.6/$3.6). Calculate Prompt Caching ROI & Batch API savings.

Qwen: Qwen3.5 397B A17B saves up to 57% on base input tokens
Zhipu AI

Z.ai: GLM 5.1

glm-5.1
Base Input Rate
$1.40 / 1M
Output Rate
$4.40 / 1M
Prompt Cache Read
$0.26 / 1M (-81.43%)
Cache Write Surcharge
$0.00 (Free write)
Batch API Discount
-50% Off
Context Window
204.8k tokens
Quality Index (MMLU)
88
Alibaba Qwen

Qwen: Qwen3.5 397B A17B

qwen3.5-397b-a17b
Base Input Rate
$0.60 / 1M
Output Rate
$3.60 / 1M
Prompt Cache Read
$0.12 / 1M (-80%)
Cache Write Surcharge
$0.00 (Free write)
Batch API Discount
-40% Off
Context Window
262.144k tokens
Quality Index (MMLU)
88
Differential Module 1

Prompt Caching ROI & Write Surcharge Break-Even Analysis

Prompt caching drastically reduces input token costs for static prefixes like system prompts, tool schemas, and document chunks. Compare caching mechanisms between Z.ai: GLM 5.1 and Qwen: Qwen3.5 397B A17B:

Z.ai: GLM 5.1 Caching Profile-81.43% read discount

  • Cached Read Price: $0.260 per 1M tokens.
  • Write Surcharge: $0.00 (automatic caching with zero write penalty).
  • Minimum Cache Prefix: 1,024 tokens.
  • Amortization Rule: Immediate net savings from first cached read call.

Qwen: Qwen3.5 397B A17B Caching Profile-80% read discount

  • Cached Read Price: $0.120 per 1M tokens.
  • Write Surcharge: $0.00 (automatic caching with zero write penalty).
  • Minimum Cache Prefix: 1,024 tokens.
  • Amortization Rule: Immediate net savings from first cached read call.
Differential Module 2

Batch API 50% Discount Offload vs Real-Time SLA

Asynchronous Batch APIs cut total token expenditures in half (50% off input and output) in exchange for non-realtime execution (up to 24-hour turnaround SLA).

Model / ArchitectureStandard Input / OutputBatch 50% Off Input / OutputTurnaround SLAOptimal Use Cases
Z.ai: GLM 5.1$1.40 / $4.40$0.70 / $2.20 (-50%)24 Hours max (typically 30m - 2h)Bulk evaluation, dataset labeling, background summarization
Qwen: Qwen3.5 397B A17B$0.60 / $3.60$0.30 / $1.80 (-50%)24 Hours max (typically 30m - 2h)Offline document translation, embedding backfills, test suites
Differential Module 3

Context Window Escalation & Tiered Pricing Architecture

Massive context windows allow ingesting entire repositories or books, but pricing models differ drastically between flat-rate vendors and tiered step-up pricing.

Z.ai: GLM 5.1 Context Capacity

Provides a 204.8k token context window with a maximum output limit of 131.072k tokens.✓ Flat-rate billing across all prompt sizes up to max context ceiling.

Qwen: Qwen3.5 397B A17B Context Capacity

Provides a 262.144k token context window with a maximum output limit of 64k tokens.✓ Flat-rate billing across all prompt sizes up to max context ceiling.

Quill Strategic Content

Real-World Production Scenarios: Monthly Spend Projections

Pre-computed monthly engineering bill projections across 3 representative enterprise application workloads:

Scenario 1

RAG Knowledge Base & Enterprise Search

100,000 queries/month, 3,500 input tokens (system + 5 retrieved chunks), 400 output tokens, 75% prompt cache hit rate.

Z.ai: GLM 5.1:$366.75/mo
Qwen: Qwen3.5 397B A17B:$228.00/mo
Delta Savings:-$138.75 (38%)
Architecture Verdict:Qwen: Qwen3.5 397B A17B delivers 38% lower monthly spend ($138.75/mo savings) for this workload profile.
Scenario 2

Multi-Turn Coding Agent & ReAct Loops

25,000 tasks/month, 8,000 input tokens (accumulating conversation context & tool schemas), 1,200 output tokens, 85% cache hit rate.

Z.ai: GLM 5.1:$201.83/mo
Qwen: Qwen3.5 397B A17B:$137.62/mo
Delta Savings:-$64.22 (32%)
Architecture Verdict:Qwen: Qwen3.5 397B A17B delivers 32% lower monthly spend ($64.22/mo savings) for this workload profile.
Scenario 3

High-Throughput Offline Data Extraction

500,000 records/month, 1,500 input tokens, 250 output tokens, 100% batch offload (24-hour turnaround SLA).

Z.ai: GLM 5.1:$714.50/mo
Qwen: Qwen3.5 397B A17B:$496.80/mo
Delta Savings:-$217.70 (30%)
Architecture Verdict:Qwen: Qwen3.5 397B A17B delivers 30% lower monthly spend ($217.70/mo savings) for this workload profile.
毫秒级实时交互模拟引擎

Z.ai: GLM 5.1 对比 Qwen: Qwen3.5 397B A17B

针对企业典型三大工程落地形态(RAG 知识库、Coding Agent 多轮、离线批量清洗)进行精确成本演算:

Live 50ms Engine
月度请求量 (Requests)100,000
单次输入 Tokens (Input)4,000
单次输出 Tokens (Output)1,000
Prompt 缓存命中率 (Cache Hit)70%
Batch API 批处理分流比例0%
Qwen: Qwen3.5 397B A17B 更便宜

预计每月节省

Z.ai: GLM 5.1$680.80$6.808// 千次请求
对比
Qwen: Qwen3.5 397B A17B$465.60$4.656// 千次请求
Developer FAQs

Frequently Asked Questions: Z.ai: GLM 5.1 vs Qwen: Qwen3.5 397B A17B

Authoritative answers on API rate limits, pricing math, break-even thresholds, and architectural migration.

1Which model is cheaper overall: Z.ai: GLM 5.1 or Qwen: Qwen3.5 397B A17B?

At base pricing, Z.ai: GLM 5.1 costs $1.4/1M input and $4.4/1M output, while Qwen: Qwen3.5 397B A17B costs $0.6/1M input and $3.6/1M output. The cheaper option depends on your input-to-output token ratio and whether prompt caching or batch discounts are utilized.

2How does Prompt Caching impact the cost of Z.ai: GLM 5.1 vs Qwen: Qwen3.5 397B A17B?

Z.ai: GLM 5.1 offers a 81.43% read discount ($0.26/1M), whereas Qwen: Qwen3.5 397B A17B provides a 80% read discount ($0.12/1M). High cache hit ratios (>70%) significantly compress the cost delta in agentic and RAG architectures.

3Can I use Batch API with Z.ai: GLM 5.1 or Qwen: Qwen3.5 397B A17B to save 50%?

Z.ai: GLM 5.1 supports 50% batch offload discounts for asynchronous 24-hour turnaround tasks. Qwen: Qwen3.5 397B A17B supports 50% batch discounts.

4What are the context window limits and tiered pricing rules for Z.ai: GLM 5.1 vs Qwen: Qwen3.5 397B A17B?

Z.ai: GLM 5.1 features a 204.8k context window with flat per-token pricing. In comparison, Qwen: Qwen3.5 397B A17B supports 262.144k tokens with flat per-token pricing.