GLM API Pricing Explained: GLM-5.2 & GLM-4-Plus Costs, Peak Rates, and Billing
Understand GLM token pricing, peak/off-peak multipliers, and how to estimate your monthly AI spending — with real cost examples.
GLM (General Language Model) by Zhipu AI is one of China's leading large language model families. It offers strong Chinese-language understanding, competitive pricing, and an OpenAI-compatible API. This guide breaks down everything you need to know about GLM API pricing — including the unique peak/off-peak multiplier system.
GLM Model Lineup and Pricing
| Model | Input / 1M tokens | Output / 1M tokens | Best For |
|---|---|---|---|
| GLM-4-Plus | $0.70 | $0.70 | General chat, Chinese tasks, production use |
| GLM-4-Flash | Free | Free | Budget applications, testing, simple tasks |
| GLM-5.2 | Peak/off-peak (see below) | Peak/off-peak | Latest model with advanced capabilities |
How GLM API Billing Works
GLM API calls are billed based on token consumption. A token is roughly 3/4 of an English word or 1-2 Chinese characters. You are billed separately for:
- Input tokens — the text you send to the model (your prompt + context)
- Output tokens — the text the model generates in response
GLM-5.2 Peak and Off-Peak Rate System
GLM-5.2 uses a unique time-based multiplier system. Your token consumption is multiplied by a rate depending on when you make the call:
| Time Period (Beijing Time, UTC+8) | Multiplier | UTC Equivalent |
|---|---|---|
| Peak hours | 3x consumption | 06:00 - 10:00 UTC |
| Off-peak hours | 2x consumption | All other times |
| Promotional period | 1x consumption | Limited-time offers |
Practical Cost Example
Say a GLM-5.2 API call uses 500 input tokens and 1,000 output tokens (1,500 total):
| Period | Multiplier | Tokens Deducted | Effective Cost |
|---|---|---|---|
| Promotional (1x) | 1x | 1,500 | Lowest |
| Off-peak (2x) | 2x | 3,000 | Standard |
| Peak 14:00-18:00 (3x) | 3x | 4,500 | 50% more than off-peak |
GLM-4-Plus: Simple Flat Pricing
Unlike GLM-5.2, GLM-4-Plus uses simple flat-rate pricing with no multipliers:
- $0.70 per 1M input tokens
- $0.70 per 1M output tokens
- No peak/off-peak surcharges
This makes GLM-4-Plus easier to budget for and predict costs. For most production applications, GLM-4-Plus is the recommended choice.
GLM-4-Plus Cost Examples
| Usage | Tokens | Cost |
|---|---|---|
| Single chat message | 300 total | $0.0002 |
| 1,000 messages/day | 300,000 total | $0.21/day |
| Monthly (30 days) | 9,000,000 total | $6.30/month |
| 10,000 messages/day | 3,000,000 total | $2.10/day |
GLM vs Other AI APIs: Price Comparison
| Model | Input / 1M | Output / 1M | Notes |
|---|---|---|---|
| GLM-4-Flash | Free | Free | Best for testing |
| DeepSeek-V3 | $0.14 | $0.28 | Cheapest paid model |
| GPT-4o-mini | $0.15 | $0.60 | Cheapest OpenAI model |
| Claude Haiku | $0.25 | $1.25 | Cheapest Claude model |
| GLM-4-Plus | $0.70 | $0.70 | Best for Chinese |
| GPT-4o | $2.50 | $10.00 | Premium OpenAI |
| Claude Sonnet | $3.00 | $15.00 | Premium Anthropic |
For a full comparison, see our AI model comparison page or the cheapest AI API guide.
How to Minimize GLM API Costs
1. Avoid Peak Hours for GLM-5.2
Batch non-urgent tasks outside 14:00-18:00 Beijing time. During peak hours, the same request costs 50% more than off-peak (3x vs 2x multiplier). For GLM-4-Plus, this is not an issue since it uses flat pricing.
2. Use GLM-4-Plus Instead of GLM-5.2
GLM-4-Plus uses flat pricing with no multipliers, making it easier to budget and often cheaper overall. Unless you specifically need GLM-5.2's capabilities, GLM-4-Plus is the safer choice.
3. Optimize Prompt Length
Input tokens are billed. Trim unnecessary context, use concise system prompts, and avoid sending redundant information. A 1,000-token system prompt costs the same as a 100-token one — but adds up at scale.
4. Set max_tokens Appropriately
Don't request 4,096 output tokens if you only need 200. Set max_tokens to a reasonable limit to prevent runaway costs from unexpectedly long responses.
5. Cache Repeated Queries
If your application sends identical queries frequently, cache the responses to avoid paying for the same computation multiple times. This is especially effective for FAQ bots and classification pipelines.
6. Use GLM-4-Flash for Testing
GLM-4-Flash is free for basic usage. Use it during development and testing to iterate without spending. Switch to GLM-4-Plus for production once your code is stable.
Code Example: Calling GLM API
from openai import OpenAI
client = OpenAI(
api_key="your-token1-us-key",
base_url="https://discount-token.com/v1"
)
# Call GLM-4-Plus
response = client.chat.completions.create(
model="glm-4-plus",
messages=[
{"role": "system", "content": "你是一个专业的中文写作助手。"},
{"role": "user", "content": "写一首关于春天的诗。"}
],
max_tokens=500
)
print(response.choices[0].message.content)
print(f"Tokens: {response.usage.total_tokens}")
Estimating Monthly Costs
Use our interactive cost calculator to estimate your monthly spending. Here are typical GLM usage patterns:
| Use Case | Model | Monthly Cost (Est.) |
|---|---|---|
| Personal project / testing | GLM-4-Flash | $0 (free) |
| Small chatbot (100 users) | GLM-4-Plus | $5-15 |
| Chinese content generation | GLM-4-Plus | $10-30 |
| Production API (10K calls/day) | GLM-4-Plus | $60-100 |
Rate Limits
| Limit | Default |
|---|---|
| Requests per minute (RPM) | 20 |
| Log retention | 7 days |
Frequently Asked Questions
How much does GLM API cost?
GLM-4-Plus costs $0.70/1M tokens for both input and output. GLM-4-Flash is free for basic usage. GLM-5.2 uses a peak/off-peak multiplier system: 3x during 14:00-18:00 Beijing time and 2x at other times.
What are GLM peak hours?
GLM peak hours are 14:00-18:00 Beijing time (UTC+8), when a 3x token consumption multiplier applies. Off-peak hours use a 2x multiplier. To minimize costs, batch non-urgent requests outside peak hours.
Is GLM API free?
GLM-4-Flash offers free basic usage. GLM-4-Plus and GLM-5.2 are paid models with per-token billing. On Token1.US, you can start with $1 and pay only for what you use.
Is GLM API compatible with the OpenAI SDK?
Yes. GLM API is fully OpenAI-compatible. Use the standard OpenAI SDK with base_url="https://discount-token.com/v1". All features work identically.
Which GLM model should I use?
For most tasks, GLM-4-Plus offers the best balance of quality and price at $0.70/1M tokens. For budget applications, GLM-4-Flash is free. GLM-5.2 is the latest model with peak/off-peak billing.
How does GLM compare to GPT and Claude?
GLM excels at Chinese language tasks and is competitively priced. GLM-4-Plus at $0.70/1M is cheaper than GPT-4o ($2.50/1M) and Claude Sonnet ($3.00/1M). For English tasks, GPT and Claude may have an edge.
How is GLM-5.2 different from GLM-4-Plus?
GLM-5.2 is the latest model with potentially improved capabilities, but uses a peak/off-peak multiplier billing system. GLM-4-Plus uses simple flat pricing and is easier to budget for. Most developers prefer GLM-4-Plus for production use.