` class can break an entire data pipeline.
A dedicated **data API** moves the complexity from your codebase to the infrastructure layer. Instead of writing brittle selectors, you define *what* you want (the schema) rather than *how* to find it (the CSS path).
1. **Define Schema** —
2. **Call Extract API** —
3. **Receive Typed JSON** —
## Quick start with AlterLab Extract API
To get started, you can follow our [Getting started guide](/docs/quickstart/installation). The core of the workflow involves the `extract` endpoint, which combines browser rendering with LLM-powered data extraction.
### Python Implementation
The following example demonstrates how to use the AlterLab Python client to retrieve structured data from a specific coin page.
```python title="extract_coingecko-com.py" {5-12}
import alterlab
client = alterlab.Client("YOUR_API_KEY")
# Define the structure you expect from the page
schema = {
"type": "object",
"properties": {
"ticker": {
"type": "string",
"description": "The cryptocurrency ticker symbol"
},
"price": {
"type": "string",
"description": "The current price in USD"
},
"change_percent": {
"type": "string",
"description": "The 24h percentage change"
},
"volume": {
"type": "string",
"description": "The 24h trading volume"
},
"market_cap": {
"type": "string",
"description": "The total market capitalization"
}
},
"required": ["ticker", "price"]
}
# Execute the extraction
result = client.extract(
url="https://www.coingecko.com/en/coins/bitcoin",
schema=schema,
)
print(result.data)
```
**Expected Output:**
```json
{
"ticker": "BTC",
"price": "$65,234.12",
"change_percent": "+2.4%",
"volume": "$32,104,552,123",
"market_cap": "$1,284,552,102,334"
}
```
### cURL Implementation
If you are working in a shell environment or a lightweight Go/Node.js service, use the REST endpoint. Refer to the [Extract API docs](/docs/api/extract) for full parameter details.
```bash title="Terminal"
curl -X POST https://api.alterlab.io/v1/extract \
-H "X-API-Key: YOUR_KEY" \
-H "Content-Type: application/json" \
-d '{
"url": "https://www.coingecko.com/en/coins/ethereum",
"schema": {
"type": "object",
"properties": {
"ticker": {"type": "string"},
"price": {"type": "string"},
"change_percent": {"type": "string"}
}
}
}'
```
## Define your schema
The power of the [coingecko api structured data](https://alterlab.io) workflow lies in the JSON schema. By providing a schema, you are instructing the engine to perform semantic extraction.
You don't need to know if the price is inside a `
` or a ``. You only need to describe the field. AlterLab uses the `description` field within your schema to understand the context of the data, which significantly increases accuracy for complex financial tables.
### Advanced: Batching and Async Jobs
For high-volume data pipelines—such as tracking the top 500 coins—running synchronous requests is inefficient. You should implement an asynchronous pattern using a task queue or AlterLab's batch processing capabilities.
```python title="batch_extract_coins.py" {4-10}
import alterlab
import asyncio
client = alterlab.Client("YOUR_API_KEY")
COIN_URLS = [
"https://www.coingecko.com/en/coins/bitcoin",
"https://www.coingecko.com/en/coins/ethereum",
"https://www.coingecko.com/en/coins/solana"
]
schema = {
"type": "object",
"properties": {
"ticker": {"type": "string"},
"price": {"type": "string"}
}
}
async def run_pipeline():
# Create a list of extraction tasks
tasks = [
client.extract_async(url=url, schema=schema)
for url in COIN_URLS
]
# Execute concurrently
results = await asyncio.gather(*tasks)
for res in results:
print(res.data)
if __name__ == "__main__":
asyncio.run(run_pipeline())
```
## Handle pagination and scale
When scaling your finance data pipeline, consider these three factors:
1. **Rate Limiting**: While AlterLab handles proxy rotation and anti-bot measures, you should still implement exponential backoff in your own application to respect the target site's stability.
2. **Cost Management**: Every extraction has a cost. You can check our [AlterLab pricing](/pricing) to model your monthly spend. We recommend using the `estimate` endpoint during development to verify your schema complexity.
3. **Data Integrity**: Use the schema to enforce types. If a price is expected as a number but arrives as a string with a "$" symbol, use your post-processing logic to clean it, or update your schema description to request a numeric format.
- **99.2%** — Extraction Accuracy
- **1.4s** — Avg Response Time
- **100%** — Typed JSON Output
## Key takeaways
* **Stop parsing HTML manually**: Use a schema-based extraction approach to build resilient pipelines.
* **Leverage semantic extraction**: Describe your fields in the JSON schema to let the engine handle the heavy lifting.
* **Scale with async**: Use asynchronous patterns to process multiple CoinGecko pages concurrently.
* **Control costs**: Use the estimate API to preview the cost of your extractions before they run.
Hit reply if you have questions.
AlterLab // Web Data, Simplified.
## Frequently Asked Questions
### Is there an official CoinGecko data API?
CoinGecko offers an official API with various tiers, but it often has strict rate limits and payload restrictions. AlterLab provides an alternative for extracting specific, structured JSON directly from public web pages when official endpoints do not meet your specific schema requirements.
### What CoinGecko data can I extract with AlterLab?
You can extract any publicly visible financial data, such as ticker symbols, current prices, 24h change percentages, trading volume, and market capitalization. AlterLab returns this data as validated, typed JSON based on your provided schema.
### How much does CoinGecko data extraction cost?
AlterLab uses a pay-as-you-go model where you only pay for the data you retrieve. You can estimate costs before execution using our Estimate API, and there are no monthly minimums or expiring balances.
## Related
- [Binance Data API: Extract Structured JSON in 2026]()
- [How to Scrape Grubhub Data: Complete Guide for 2026]()
- [How to Scrape MarketWatch Data: Complete Guide for 2026]()