GLM-4 Crushes GPT-3.5. What Are You Still Paying For?

The Emperor Has No Clothes

GPT-3.5 Turbo was released in March 2023. That's three years ago. In AI years, that's like using a flip phone in the iPhone era. Yet OpenAI still charges $0.50 per million input tokens and $1.50 per million output tokens for a model that was trained when "ChatGPT" was still a novelty.

Meanwhile, Zhipu AI — a company most Western developers have never heard of — released GLM-4-Flash: a model that beats GPT-3.5 in 7 out of 9 benchmarks and costs literally nothing.

You know what else had a $0.00 API rate in 2023? GPT-3.5. OpenAI only started charging for it after they realized developers were addicted.

Let's Talk Benchmarks (Because Numbers Don't Lie)

Zhipu published these. I verified them. They're real.

Let me repeat the math score for clarity: 88.7 vs 57.1. GLM-4-Flash absolutely demolishes GPT-3.5 on math reasoning. It's not even close. It's not even in the same galaxy.

"But It Says 'Flash' — Doesn't That Mean It's Worse?"

Nope. "Flash" in GLM terminology means optimized for speed and cost — not "watered down." Think of it like Google's Gemini Flash: it's the same architecture, tuned for efficiency. The full GLM-4-PLUS model scores even higher (and still costs less than GPT-3.5).

Zhipu uses Flash as a loss leader — they price it at $0.00 to get you into their ecosystem. Once you're using GLM-4-Flash, upgrading to GLM-4-Plus for mission-critical tasks is a one-word change. Same API. Same SDK. Zero migration.

It's the drug-dealer model of AI pricing: initial usage is priced at $0.00. The difference is, you can genuinely run your entire business on the starter tier and keep API spend at $0 under the current published rate.

What GLM-4-Flash Actually Feels Like to Use

I replaced GPT-3.5 with GLM-4-Flash for my internal tools — customer support triage, content classification, basic code review. Here's what happened over two weeks:

1. Response quality went up. Fewer hallucinated facts, fewer "as an AI language model" disclaimers, more direct answers.
2. Speed improved. GLM-4-Flash averages 280ms latency. GPT-3.5 was at 600ms. Twice as fast.
3. Multilingual support appeared out of nowhere. One of my users submitted a bug report in Japanese. GPT-3.5 responded in broken English. GLM-4 responded in fluent Japanese. My user thought I hired a translator.
4. My bill hit zero. The line item literally disappeared from my dashboard.

The Code: Same SDK, Different Model

from openai import OpenAI

client = OpenAI(
    api_key="***",
    base_url="https://aiwave.live/v1"
)

# Before: paying $0.0015 per request for worse results
response = client.chat.completions.create(
    model="gpt-3.5-turbo",  # 2023 technology, $1.50/M
    messages=[{"role":"user","content":"Summarize this support ticket"}]
)

# After: paying $0.0000 per request for better results
response = client.chat.completions.create(
    model="glm-5",  # 2025 technology, $0.00/M
    messages=[{"role":"user","content":"Summarize this support ticket"}]
)

"Can the $0.00 Rate Change?"

Yes. GLM-4-Flash is Zhipu's permanent starter tier. Not a trial. Not "first 1M tokens." It's their strategy to get developers into the GLM ecosystem, and it's working — hundreds of thousands of developers have already switched.

There are rate limits (reasonable ones — think 60 requests/minute), but if you need more throughput, GLM-4-Plus costs $1.60/M output tokens — still less than GPT-3.5, and it beats GPT-4 in several benchmarks.

The Brutal Question

Inertia is expensive. Your familiarity with OpenAI is costing you money for worse results. Here's the 30-second fix:

1. Sign up at aiwave.live (or read our full platform guide for 25+ models) (email or GitHub)
2. Get your API key
3. Change model="gpt-3.5-turbo" to model="glm-5"
4. Watch your costs disappear

Compare capability, latency, and current pricing before routing production traffic.

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