How do I use URL templates?

Use curly braces for placeholders that match your CSV headers. For example, /products/{id}/shops/{shop_id} will replace {id} and {shop_id} with values from columns named 'id' and 'shop_id' in your CSV.

How many concurrent requests can I run?

You can configure 1-50 concurrent workers. Higher concurrency is faster but may overwhelm the target server. Start with 5-10 for most use cases.

Bulk API Invoker

Request Configuration

Use {column_name} for placeholders that match CSV headers

Concurrent Workers: (1-50)

Headers

Headers can also use {placeholders}

Request Body Template

(for POST/PUT/PATCH)

JSON body with placeholders. Non-string values like numbers work too.

CSV Data

Upload CSV

Paste CSV or upload file. First row = headers.

Use CORS Proxy

Show Headers Show Body

Bulk API Testing Tool

Execute multiple API calls using data from a CSV file. Useful for controlled batch operations, data migration, test setup, and validating endpoints with different inputs. Request generation and result handling happen in your browser.

How to Use

Enter your URL template with placeholders like /api/products/{id}
Paste or upload CSV data where column headers match your placeholder names
Optionally configure headers and body template (also supports placeholders)
Set the number of concurrent workers (higher = faster, but may overwhelm the server)
Click "Start Execution" and watch the progress

Example

URL Template:

https://api.example.com/products/{product_id}/inventory

CSV Data:

product_id,warehouse
SKU001,WH-A
SKU002,WH-B
SKU003,WH-A

Body Template (for POST):

{"warehouse": "{warehouse}", "check_stock": true}

One CSV row, one HTTP request

Column names become placeholders in the URL, HTTP headers, and request body. That makes the runner useful for targeted migrations, record validation, test-data setup, cache warming, and controlled administrative updates.

Concurrency you can control

Choose 1–50 browser workers, pause or stop the run, and watch per-request status, timing, and response data. Start conservatively: this is a batch request utility, not a capacity or load-testing substitute.

Browser CORS is still enforced

If the API does not allow browser origins, use the optional Holy CORS bridge on your own machine. Requests go to the endpoint you configure and are not relayed through Bug Days servers.

For a single exploratory call, use the REST API client. For WSDL operations and XML envelopes, use the online SOAP client.