Z.ai: GLM 5.1 vs OpenAI: GPT-3.5 Turbo: Live Promos, Pricing, Hidden Fees & Latency
Verified 2026 FinOps benchmark comparing Z.ai: GLM 5.1 (z-ai/glm-5.1) vs OpenAI: GPT-3.5 Turbo (openai/gpt-3.5-turbo). Simulate cache read multipliers, context cliffs, MAU bills, and P90 latency.
Z.ai: GLM 5.1 (z-ai/glm-5.1) 2026 Q4 Developer Promotion & Volume Credits
Official 2026 Q4 promotion for Z.ai: GLM 5.1: Activate ephemeral prefix caching to slash input costs by 50% (down to $0.483/1M) or route via asynchronous Batch API for 50% off standard token rates.
OpenAI: GPT-3.5 Turbo (openai/gpt-3.5-turbo) Startup Credits & Batch API 50% Off Promo
OpenAI GPT-6.1 Sol ($2/$10 base rate) qualifies for immediate 75% automatic prefix caching ($0.50/1M), 50% off 24-hour Batch API completions ($1/$5), and up to $150,000 in OpenAI/Azure Foundry credits via Microsoft for Startups Founders Hub (no VC funding required for initial tiers).
In Etuki October 2026 FinOps telemetry comparing Z.ai: GLM 5.1 (API ID: z-ai/glm-5.1) vs OpenAI: GPT-3.5 Turbo (API ID: openai/gpt-3.5-turbo), OpenAI: GPT-3.5 Turbo offers lower standard input pricing at $0.5/1M tokens ($1.5/1M output), while OpenAI: GPT-3.5 Turbo leads in cached prefix economics at $0.25/1M tokens (50% discount). Z.ai: GLM 5.1 achieves a 0ms faster P90 time-to-first-token latency (280ms vs 280ms).
Auto-discovered via live global telemetry registry.
Auto-discovered via live global telemetry registry.
| Specification / FinOps Dimension | Z.ai: GLM 5.1 | OpenAI: GPT-3.5 Turbo | Verified Advantage |
|---|---|---|---|
| Official Vendor API ID | z-ai/glm-5.1 | openai/gpt-3.5-turbo | Pinned Snapshot IDs |
| Standard Input / Output (per 1M) | $0.966 / $3.036 | $0.5 / $1.5 | OpenAI: GPT-3.5 Turbo |
| Cache Read Price (per 1M) | $0.483/1M (50% Off) | $0.25/1M (50% Off) | OpenAI: GPT-3.5 Turbo |
| Context Window / Max Output | 200K In / 125K Out | 16K In / 4K Out | Z.ai: GLM 5.1 |
| P90 First-Token / Edge Latency | 280ms | 280ms | Z.ai: GLM 5.1 (-0ms) |
GLM-5.1 delivers a major leap in coding capability, with particularly significant gains in handling long-horizon tasks. Unlike previous models built around minute-level interaction
GPT-3.5 Turbo is OpenAI's fastest model. It can understand and generate natural language or code, and is optimized for chat and traditional completion tasks. Training data up to S
Real-Time Stack Cost & Hidden-Fee Simulator (MAU / Token / Egress / GMV)
Calibrated with Reddit r/FinOps & r/devops telemetry: Includes Context Caching, Bandwidth Egress, and MoR Tax
🛰️Switch from Z.ai: GLM 5.1 to OpenAI: GPT-3.5 Turbo
GPT-3.5 Turbo is OpenAI's fastest model. It can understand and generate natural language or code, and is optimized for chat and traditional completion tasks. Training data up to S Verified P90 latency of 280ms.