Throttle + EasyPost
Show live EasyPost carrier rates at Throttle checkout: connect your API key, set a ship-from address, and buyers choose from real carrier services.
What the integration does
With EasyPost connected, cart and checkout shipping options come from the carrier accounts in your EasyPost account. Each rate shows the carrier and service, the price, and the delivery estimate, and the option the buyer picks is priced onto the order.
Throttle requests rates with your ship-from location, the buyer’s destination, and the order’s total weight, summed from each line item and converted to ounces for EasyPost.
Setting it up
- Open Shipping & Tax → Carriers and add EasyPost.
- Paste an EasyPost API key — the test key (
EZTK…) for testing, the production key (EZAK…) for real rates. Throttle verifies it before saving. - Set your ship-from address in shipping settings.
- Switch the application’s shipping mode to use the connected provider.
Each workspace environment keeps its own connection, so test and production can hold different keys.
If EasyPost doesn’t answer
By default checkout falls back to the shipping rates you’ve configured in Throttle when EasyPost errors or takes longer than five seconds, and flags that it did. Make it strict if you’d rather stop the checkout. Five consecutive failures mark the connection unhealthy and alert your admins.
Good to know
- Rates only. Buying labels and tracking stay in EasyPost or your fulfillment tool — see ShipStation for warehouse handoff.
- Rates are quoted on one standard parcel using the order’s total weight; per-item dimensions aren’t sent yet. Pass weights on your line items.
- If no carrier accounts return rates, buyers see no options — that’s treated as an answer, not an outage.