Shipment Estimate
Available rates
USPS Ground Advantage
$8.17
Est. 3 days · lowest rate
UPS Ground
$9.19
Est. 3 days
UPS 2nd Day Air
$16.85
Est. 2 days
USPS Priority
$18.14
Est. 3 days
FedEx Express Saver
$22.85
Est. 3 days · guaranteed
For teams building shipping into their workflow
WhiteFlow runs rate estimates, print-ready labels, refunds, and tracking together.
Each client gets isolated credentials and a consistent carrier response. Validate in sandbox before moving to production.
Step one
Structured
Input
Submit origin, destination, and parcel details to receive a list of available rates across multiple carriers, each with pricing and estimated delivery time.
Step two
Trimmed
Output
Select a rate and purchase the shipment in one call. A print-ready label is returned immediately in the response.
Step three
Complete
Lifecycle
Check tracking status at any time or cancel a shipment and request a refund when the carrier allows it.
Current system
WhiteFlow is a multi-carrier shipping API built for teams that need rate comparison, label generation, and tracking in one place.
Per-client isolated credentials
Test and production environments
Refund support where carriers allow