Wuunder Rest API suite
One integration. 300+ carriers. 120,000+ preconfigured shipping services. The Wuunder REST APIs connect your webshop, marketplace, ERP, or WMS with the entire shipping chain: from dynamic checkout options and automatic carrier selection to label generation, customs documents, tracking, and returns. Use your own carrier contract or ship directly through our resell partner.
Why developers choose Wuunder's API suite
Wuunder gives you access to 300+ carriers and 120,000+ preconfigured services. Our carrier library is centrally maintained: when carriers change rates, transit times, or surcharges, we update them. You don't.
What sets us apart: GreenChoice, our smart carrier selection algorithm, automatically matches every order with the optimal carrier and best delivery moment, based on speed, cost and CO₂ reduction. By spreading deliveries across the week, we flatten the Monday peak in the warehouse and the Tuesday peak at the carrier. Fewer temp staff needed, lower operational costs. The result: fewer failed deliveries, fuller vans and a supply chain that works for your business, your warehouse, your carriers and the environment.
Checkout
Display options in your e-commerce shop that increase conversion by 30%. Use your checkout in a way that also saves costs in your warehouse.
- Shipping Options: Dynamically display available delivery options based on the delivery matrix, destination, weight, volume, and order value, including carrier, price, delivery times, and sustainability label (GreenChoice)
- Nominated Day: Let customers choose a specific delivery day. We take delivery time into account and inform you of the correct pick & pack day, i.e. the carrier collection day
- Best Day Delivery | GreenChoice: Your customers choose a delivery day when the carrier is already in their street. This reduces the Monday peak in your warehouse because customers no longer have their shipments delivered next-day
- Pickup Locations: Display available PUDO locations, pickup points, and parcel lockers with address, opening hours, distance, and estimated delivery date
- PuzzlPack: Automatically calculate the optimal packaging option based on order contents and determine whether the parcel is suitable for a locker, pickup point, or (home) delivery
- Checkout API documentation
Ship
Use services in your warehouse that save costs. Pick & pack orders in the right packaging so you ship less air and save on transport costs. Work faster because labels can be booked well before you need them. Choose the cheapest or fastest service based on your own or our standard rates.
- Order Management: Create, modify, and retrieve orders and shipments including real-time status updates
- PuzzlPack: Calculate the optimal packaging option per shipment based on item dimensions and weight
- Available Carrier Services: Retrieve all available shipping options, filtered by destination, volume, weight, and packaging type.
- Rate Calculation (Shipping Rates): Automatically calculate the cheapest or fastest shipping option and receive the transport purchase price instantly
- Multi-carrier & Flexible Shipment Management: Support for label generation, multi-parcel shipments, and flexible carrier selection based on business rules
- Ship: Generate shipping labels (ZPL, PDF, PNG), paperless customs documents, and monitor the booking and warehouse process in real time
Track
Communicate with the recipient, carrier, and sender about the shipment status. Receive track & trace status emails and benefit from additional status codes added by Wuunder, such as number of days delayed.
- Enriched Tracking: Track shipments with enhanced carrier status information, including predicted delays, deviations from the promised delivery date, and proactive notifications
- Track & Trace Email Communication in Your Own Branding: Communicate clearly to the order recipient about the arrival of their order
- Mail Forward Service: Block unclear carrier emails or replace them with your own email communication
- Advanced Analytics: In-depth analysis of the complete delivery journey per customer to proactively improve NPS and make delivery performance measurably better
Returns
A portal easily accessible via a link from your webshop where your customer can simply return or exchange order items.
- Branded Self-Service Returns Portal: A fully customizable digital portal where customers easily register their returns, including return reasons and product photos
- Automated Exchange & Store Credit: Retain revenue by automatically offering customers an exchange or store credit instead of a refund
- Returns Policy & Workflow Automation: Configurable rules and triggers that eliminate manual processing and accelerate the entire returns process
- Multi-carrier & Flexible Returns Management: Label generation for return shipping via multiple carriers, with flexible routing and tracking
From checkout to return in 4 steps
Q: What is a multi-carrier shipping API?
A: A multi-carrier shipping API is a single integration point that connects your system to multiple carriers simultaneously. Instead of building and maintaining separate connections with PostNL, DHL, DPD, UPS, and others, you integrate once with Wuunder and get access to 300+ carriers through one standardized interface.
Q: How long does it take to integrate Wuunder's API?
A: Most custom integrations go live within 1-2 days. Our REST API follows standard conventions and our sandbox environment lets you test without touching live shipments. For e-commerce platforms like Shopify or WooCommerce, you can use our ready-made plug-ins and go live within minutes.
Q: Can I use my own carrier contracts with Wuunder's API?
A: Yes. Connect your existing PostNL, DHL, DPD, or any other carrier contract. Wuunder calculates rates based on your negotiated prices, or use our standard rates. No contract? Use our default resell partner for immediate access to competitive rates without setup costs.
Q: What makes Wuunder's APIs unique?
A: Wuunder works with meta tags, allowing you to include your own data fields in the request. You can then use these data fields to book specific carriers or services.
Q: Does the API support international shipping and customs?
A: Yes. Wuunder automatically generates customs documents (CN23, commercial invoices) and supports paperless customs with carriers that offer this. Ship to 220+ countries via parcel, express, pallet, or groupage services.
Q: Can I calculate shipping rates in real time via the API?
A: Yes. Our Rates endpoint returns all available carrier options with prices including most surcharges and transit times. Filter by cheapest service, fastest service, delivery to parcel shop or parcel locker, or by a specific option such as insurance, signature on delivery, evening delivery, etc.
Q: What label formats does the API support?
A: ZPL (if available from the carrier) and PDF. Multi-parcel shipments generate all labels in a single response. Transfer documents for the driver are automatically included for every pickup.
Q: How does GreenChoice work via the API?
A: Call our Checkout API with order details. GreenChoice intelligently spreads orders across the week so your warehouse has fewer peaks and carriers deliver more efficiently. 88% of consumers opt in. You display the options, we handle the logic.
Start today with the smartest shipping platform
30% conversion increase by displaying sustainable delivery options. This immediately reduces warehouse peaks, saving you costs. Use 120,000+ preconfigured transport services. Want to know more? We're happy to help you personally!