` class changes), you describe the *shape* of the data you want.
1. **Define Schema** —
2. **Call Extract API** —
3. **Receive Typed JSON** —
## Quick start with AlterLab Extract API
The [Extract API docs](/docs/extract) provide the full specification for making these calls. You can interact with the API via Python or direct cURL commands.
### Python Implementation
Using the Python client is the most efficient way to integrate extraction into existing data pipelines.
```python title="extract_capterra-com.py" {5-12}
import alterlab
client = alterlab.Client("YOUR_API_KEY")
# Define the exact shape of the data you need
schema = {
"type": "object",
"properties": {
"product_name": {
"type": "string",
"description": "The name of the software product"
},
"rating": {
"type": "string",
"description": "The star rating value"
},
"review_count": {
"type": "string",
"description": "The total number of reviews"
},
"category": {
"type": "string",
"description": "The software category"
},
"verified_purchase": {
"type": "boolean",
"description": "Whether the review is a verified purchase"
}
}
}
result = client.extract(
url="https://capterra.com/p/12345/product-name/",
schema=schema,
)
print(result.data)
```
**Expected Output:**
```json
{
"product_name": "Example CRM",
"rating": "4.8",
"review_count": "1,240",
"category": "Customer Relationship Management",
"verified_purchase": true
}
```
### cURL Implementation
For shell scripts or lightweight services, use the POST endpoint directly.
```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://capterra.com/p/12345/product-name/",
"schema": {
"type": "object",
"properties": {
"product_name": {"type": "string"},
"rating": {"type": "string"},
"review_count": {"type": "string"}
}
}
}'
```
## Define your schema
The core strength of a data API is the schema. Unlike a web scraper that returns a messy blob of HTML, the Extract API uses the schema to perform intelligent extraction.
When you provide a JSON schema, the engine:
1. Navigates the page to find relevant nodes.
2. Uses LLM-based reasoning to map text to your specific keys.
3. Validates the output against your types (e.g., ensuring a `boolean` is actually `true` or `false`).
This eliminates the "selector maintenance" cycle that plagues traditional scraping. If Capterra changes their UI from a `
` to a ``, your pipeline remains unbroken because the underlying semantic data hasn't changed.
## Handle pagination and scale
If you are building a comprehensive dataset, you will need to handle multiple pages of reviews. For high-volume extraction, do not use synchronous loops. Instead, utilize asynchronous jobs to maximize throughput.
```python title="batch_extraction.py" {4-9}
import alterlab
client = alterlab.Client("YOUR_API_KEY")
urls = [
"https://capterra.com/p/1/product-a/",
"https://capterra.com/p/2/product-b/",
"https://capterra.com/p/3/product-c/"
]
# Submit jobs in parallel
jobs = [
client.extract_async(url=u, schema=my_schema)
for u in urls
]
# Poll for results or use webhooks
for job in jobs:
print(job.get_result())
```
When scaling, keep an eye on your [AlterLab pricing](/pricing). Costs are calculated per extraction. You can use the `POST /v1/extract/estimate` endpoint to calculate costs before running large batches, which is critical for managing budget in production environments.
- **99.2%** — Extraction Accuracy
- **1.4s** — Avg Response Time
- **100%** — Typed JSON Output
## Key takeaways
* **Schema over Selectors**: Use JSON schemas to define data shapes instead of fragile CSS/XPath selectors.
* **Data API vs Scraper**: Treat your extraction as a structured data request rather than a web scraping task.
* **Scale Asynchronously**: For large-scale Capterra data extraction, use async jobs and webhooks to prevent bottlenecking.
* **Predictable Costs**: Use the estimation endpoint to manage spend when running large-scale batch jobs.
Hit reply if you have questions.
AlterLab // Web Data, Simplified.
## Frequently Asked Questions
### Is there an official Capterra data API?
Capterra does not offer a public, self-service API for third-party developers. AlterLab provides a data API alternative that retrieves publicly accessible information and returns it in a structured JSON format.
### What Capterra data can I extract with AlterLab?
You can extract any publicly visible information, such as product names, star ratings, review counts, categories, and verified purchase status. The extraction is guided by a JSON schema you define.
### How much does Capterra data extraction cost?
AlterLab uses a pay-for-what-you-use model with no minimum commitment. Costs depend on the complexity of the extraction and the LLM orchestration required, with full details available on our pricing page.
## Related
- [Lowe's Data API: Extract Structured JSON in 2026]()
- [How to Migrate from Scrapfly to AlterLab: Step-by-Step Guide \(2026\)]()
- [Scaling Web Scraping Pipelines for High-Volume Data]()