"What's a cheaper alternative to the ChatGPT API?" is arguably the single most-asked pricing question in developer AI conversations in 2026. The good news: you do not need to give up the OpenAI SDK, streaming, or tool-calling to cut costs. These seven models are all OpenAI-compatible and cost a small fraction of GPT-5.5 list pricing.
| # | Model | Input | Output | Best for |
|---|---|---|---|---|
| 1 | qwen3.5-flash (Alibaba) | $0.048 | $0.26 | Cheapest capable chat, 1M context |
| 2 | deepseek-v4-flash | $0.08 | $0.17 | Best price/performance, 1M context |
| 3 | doubao-seed-2.0-lite (ByteDance) | $0.075 | $0.45 | High-volume lightweight tasks |
| 4 | hy3 (Tencent Hunyuan) | $0.18 | $0.72 | Balanced general chat |
| 5 | minimax-m2.5 | $0.27 | $1.08 | Long-running agent loops |
| 6 | glm-5 (Zhipu) | $0.60 | $1.92 | Strong reasoning at mid price |
| 7 | kimi-k2.5 (Moonshot) | $0.60 | $3.00 | Coding & long-context agents |
Reference point: OpenAI GPT-5.5 list pricing is roughly $5 input / $15 output per 1M tokens (confirm on OpenAI's pricing page). Every model above is at least ~10x cheaper on input; qwen3.5-flash is ~100x cheaper.
from openai import OpenAI
client = OpenAI(api_key="sk-novai-your-key", base_url="https://aiapi-pro.com/v1")
resp = client.chat.completions.create(
model="qwen3.5-flash", # swap to any of the seven
messages=[{"role": "user", "content": "Summarize this contract"}],
)
NovAI passes provider list pricing through with zero platform fee, so the table above is exactly what you pay. New accounts get $2 free credit, no card required.
Bottom line: you can replace most ChatGPT-API workloads with an OpenAI-compatible Chinese model at 1/10th to 1/100th the cost, without touching your SDK code.
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