How to choose cardboard boxes
This guide helps you choose the right shipping box for your needs - whether you're sending fragile electronics, books, or bulk items. Learn about box strength, fluting types, dimensions, and use cases. Use the quick checklist and FAQs to match your product with the ideal box type. Then explore our product categories to buy the right box for shipping.
Cardboard box fluting explained
Fluting is the wavy layer inside corrugated cardboard that affects rigidity, cushioning, and stacking strength. Choose the right flute based on your product’s weight and shipping conditions:
Single
- Resistant
- For light and less fragile products
- Great for short-distance shipping
- Supports loads up to 30 kg
Reinforced double
- Extra Resistant Export Quality
- Stronger and more resitant than double wall
- Recommended for export and demanding shipping conditions
- Supports loads up to 70 kg
Triple
- Exceptional Stength Export Quality
- Heavy-duty performance
- For highly fragile products and items
- Recommended for demanding transport, international shipping, and long-term storage
- Supports heavy loads up to 500 kg
Our expert advice
When choosing the best shipping boxes, focus on four key factors:
- Product weight – use single wall for light to medium goods, and double or triple wall for heavier loads.
- Shipping conditions – single or double wall for postal or courier deliveries; triple wall for export or pallet shipping.
- Box size – select internal dimensions close to your product to minimise void fill and costs.
- Intended use – postal for small items, archive for documents, heavy-duty for industrial packaging. The right box choice improves protection, efficiency and sustainability.
Choosing the right fluting for your needs
When choosing among cardboard box flute types, it is essential to consider both the weight of the product and the shipping conditions. Indeed, it is true that the heavier the product, the stronger the fluting needs to be. Likewise, long-distance shipping, courier delivery, or international transport will require more robust fluting to ensure optimal protection of the contents.
| Single | Double | Reinforced Double | Triple | |
|---|---|---|---|---|
| By Weight | ||||
| Lightweight (up to 30 kg) |
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| Heavy and/or fragile (up to 40 kg) |
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| Very heavy and/or fragile (up to 70 kg) |
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| Very heavy and fragile (up to 500 kg) |
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| By Shipping Type | ||||
| Shipping on pallet | ||||
| Postal shipping | (depending on dimensions) | |||
| Shipping by carrier | ||||
| Shipping internationally | ||||
Recommended choice for optimal performance
Shipping Box Size Guide
How to measure a box:
(The sizes shown always refer to the internal measurements)
Length (L) - Longest side
Width (W) - Shorter side
Height (H) - Vertical dimension (excluding flaps)
How to choose the right shipping box
Measure your item’s length, width and height, then add 2–5cm to each dimension to allow space for protective packaging. This helps prevent pressure on the item and reduces movement in transit. Select a box that closely matches these adjusted measurements; a box that’s too large can cause shifting, while one that’s too small may not fit or could damage the contents.
Royal Mail size guidance (UK):
- Large Letter: up to 353 × 250 × 25mm (max 750g)
- Small Parcel: up to 450 × 350 × 160mm (max 2kg)
- Medium Parcel: up to 610 × 460 × 460mm (max 20kg)
Always measure the outer packed box to confirm the size category before posting.
From a choice of over 900!
Enter the interior dimensions you are looking for:
(Length x Width x Height)
Choosing the right types of boxes for your needs
Additional factors should be considered when selecting the box best suited to your needs:
- Shape of objects : for flat, long, or irregularly shaped items, opt for an adaptable box that fits perfectly.
- Nature of the items : protect fragile items with boxes that offer ample space for cushioning, ensuring your shipments arrive safely.
- Quantity of items : If you have many items to ship or store, it’s best to choose large boxes or divide them into several smaller boxes.
Discover RAJAPACK’s wide range of boxes, each designed to suit different types of products:
Triple wall shipping boxes
For industrial-strength protection for valuable and heavy duty shipments.
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Why choose a customised box for your products?
Protect and enhance the value of your products with custom-made boxes and crates, crafted to fit your product dimensions and printed with your brand. By showcasing your logo, and core messages, you enhance your brand image and create a memorable experience for your customers with every order.
With the guidance of our experts, you get personalised support to design packaging that perfectly meets your needs. From concept to production, we bring your ideas to life with fully tailor-made solutions.
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