Free tool · Parcel size guide
What size is your parcel?
Enter your parcel’s dimensions and weight to see which size band it falls into with Royal Mail, Evri, DPD, FedEx and Spring, and whether it’s too big to send.
Parcel size calculator
Which size band does it fit?
Measure the outside of the packed parcel, not the product, and weigh it with its packaging. Choose a courier, or compare them all.
Your parcel
Sizes are each courier’s published standard limits. Contract services, surcharges and some destinations can differ, so always check before you book.
How to measure
Measure it the courier’s way.
Pack it first
Measure the finished parcel, including the box, padding and any bulge.
Find the length
The length is always the longest side. The other two are width and height.
Work out the girth
Girth is the distance round the parcel: (width + height) × 2. Add the length for “length + girth”.
Weigh it
Weigh it packed. Couriers may charge on volumetric weight (L × W × H ÷ 5,000) if it’s higher.
Size and weight limits
Every courier’s limits, side by side.
Published standard limits for sending from the UK. Checked October 2026.
| Letter | 24 × 16.5 × 0.5cm, up to 100g |
| Large letter | 35.3 × 25 × 2.5cm, up to 750g |
| Small parcel | 45 × 35 × 16cm, up to 2kg |
| Medium parcel | 61 × 46 × 46cm, up to 20kg |
| Parcelforce | Up to 1.5m long, 3m length + girth, 30kg |
| Parcelforce large | Up to 2.5m long, 4m length + girth, 30kg |
| Letter | 24 × 16.5 × 0.5cm, up to 100g |
| Large letter | 35.3 × 25 × 2.5cm, up to 750g |
| Small parcel | Length + width + height up to 90cm, no side over 60cm, up to 2kg |
| Medium parcel | 61 × 46 × 46cm, up to 20kg (International Tracked only) |
| Parcelforce Worldwide | Up to 1.5m long, 3m length + girth, 30kg |
| Postable | Up to 35 × 23 × 3cm, up to 1kg |
| Small parcel | Up to 45 × 35 × 16cm, up to 2kg |
| Parcel | Up to 120cm long, and length + 2 × (the two shortest sides) under 245cm, up to 15kg |
| Locker | Up to 62 × 39 × 57cm |
| Parcel | Up to 1m long and 230cm girth, up to 30kg |
| Shop drop-off | Up to 20kg |
| Package | Up to 274cm long and 330cm length + girth, up to 68kg |
| Heavier | Over 68kg goes as FedEx freight |
| Packet | Length + width + height up to 90cm, no side over 60cm, up to 2kg |
| Tracked parcel | Up to 20kg, length + width + height usually up to 120cm (varies by destination) |
FAQs
Parcel sizes, answered.
What counts as a large letter?
With Royal Mail, a large letter is up to 35.3cm long, 25cm wide and 2.5cm thick, and weighs up to 750g. A4 documents, magazines and slim clothing in a mailer bag often fit.
What is girth?
Girth is the distance around the parcel at its widest point: (width + height) × 2. “Length + girth” adds the longest side on top.
What is volumetric weight?
Couriers charge for space as well as weight. Volumetric weight is usually length × width × height in cm, divided by 5,000. If it’s higher than the actual weight, you may be charged on it instead.
What happens if my parcel is too big?
Oversized or overweight parcels can be surcharged, returned or refused. Use a bigger size band, a different courier, or ship it on a pallet.
Do Scale 3PL clients have to measure every parcel?
No. We pick the right packaging and the right courier service for every order, so you don’t pay for a bigger size band than you need.
Let us pick the right service.
We choose the right box and the best courier for every order, from large letters to pallets.