How to Measure Your Dog for a Lead: Width, Length and Clip Size
Most sizing mistakes come from measuring the wrong thing. People reach for a tape measure and check how tall their dog is, when the two numbers that actually decide which lead you need are your dog's weight and how you like to walk.
This takes about two minutes and no tape measure at all.
Step 1: weight, and an honest view of pulling
Width is matched to the load your dog can put through the lead, which is weight multiplied by determination. Weigh your dog if you do not know (most vets will let you use the scales in reception for free), then be honest about the second part.
| Weight | Width | Clip | Typical breeds |
|---|---|---|---|
| 5–12 kg | 1.6 cm | Small | Pug, Jack Russell, Dachshund, Shih Tzu, Toy Poodle, Yorkshire Terrier |
| 10–20 kg | 1.6 cm | Medium | Whippet, French Bulldog, Cocker Spaniel, Beagle, Corgi, Cockapoo |
| 18–40 kg+ | 2.5 cm | Large | Labrador, Border Collie, German Shepherd, Boxer, Husky, Doberman |
The ranges overlap deliberately. A 12 kg terrier that throws itself at every squirrel belongs in the medium clip; a gentle 20 kg lurcher is perfectly served by the small one. If you are between two, go up.
Step 2: how you walk
Length is not about your dog at all. It is about where you walk and whether you want your hands free.
- Short (100–150 cm) — pavements, roadsides, towns, training. You want the dog close and the lead short enough to shorten further in a hurry. It cannot be worn across the body.
- Medium (150–260 cm) — parks, woods, beaches, loose-lead walking, and wearing hands-free across your body. If you are buying one lead, this is the one.
- Long line (5 m, 10 m, 15 m) — recall training and free walks in open space. Not a walking lead, and never worn across the body. Most people own one as well as a Short or Medium rather than instead of one.
Short and Medium meet at 150 cm rather than overlapping, so each one does something the other cannot: only Short goes genuinely short, and only Medium is long enough to wear cross-body. Pick for the walk you do most often, not the one you do occasionally.
If you want it worn across the body, note that how much lead is left for your dog depends on your own height and how closely your dog walks. A taller owner uses more of the range.
Step 3: clip size
Clip size follows width, but it is worth a separate thought for small dogs. A large trigger clip on a 6 kg dachshund is a surprising amount of metal swinging near their face, and the weight pulls the collar sideways. For small breeds, a smaller clip is more comfortable and perfectly strong enough.
Going the other way, an undersized clip on a big dog is the most common point of failure on any lead. If you are sizing for a Labrador or anything larger, do not economise here.
Common sizing mistakes
- Measuring height instead of weight. A greyhound is tall and light; a bulldog is short and heavy. The lead cares about the second number.
- Buying for the puppy you have now. A Labrador puppy at 12 kg will be 30 kg within a year. Buy for the adult dog unless you are happy to buy twice.
- Choosing length by dog size. Length is about your walk, not your dog. Small dogs are often walked on pavements, which argues for shorter, not for thinner.
- Buying a long line as a walking lead. Five metres of line on a pavement is a trip hazard for you and everyone else. A long line is a training tool for open ground.
- Forgetting the adolescent phase. Many breeds pull hardest between six and eighteen months, well before they reach full weight. Size for that phase, not for the calm dog they become.
- Assuming a harness changes the sizing. It changes where the force goes, not how much there is.
Quick reference by breed
- Small, 1.6 cm, small clip: Chihuahua, Pug, Dachshund, Jack Russell, Shih Tzu, Maltese, Toy Poodle, Yorkshire Terrier, Bichon Frise, Italian Greyhound
- Medium, 1.6 cm, medium clip: Cocker Spaniel, Springer Spaniel, French Bulldog, Beagle, Corgi, Whippet, Cockapoo, Border Terrier, Miniature Schnauzer, Cavalier
- Large, 2.5 cm, large clip: Labrador, Golden Retriever, German Shepherd, Border Collie, Boxer, Husky, Doberman, Dalmatian, Weimaraner, Standard Poodle, Rottweiler, Bernese
Crossbreeds: go by weight and by which parent they take after in temperament.
What about collar size?
If you are measuring for a collar at the same time, use a soft tape around the base of the neck where the collar sits, and leave two fingers of room between the tape and your dog's neck. For a thick-coated dog, measure after a groom rather than before, or you will size to the coat rather than the dog.
Still not sure?
Our size and length guide has the full table with weight ranges and breed suggestions, and walks through both decisions in order.
If your dog genuinely sits outside standard sizing, we make custom dog leads to measure — any length, width, hardware and colour.
Otherwise, browse the lightweight waterproof dog leads for everyday walks, or the heavy duty dog leads for large breeds and strong pullers. Every lead is handmade in Dorset with free UK delivery.
Frequently asked questions
How do I measure my dog for a lead?
You do not need a tape measure. Use your dog's weight to pick the webbing width and clip size, and pick the length by how and where you walk. Those are the only two decisions.
What size lead for a puppy?
Size for the adult dog if the breed grows substantially, because the pulling phase usually arrives before full weight does. For a breed that stays small, buy for the dog you have.
What width lead for a Labrador?
2.5 cm with a large clip. Most adult Labradors are 25–36 kg and strong enough to be hard on undersized hardware.
Is a longer lead better?
Not near roads. More lead means more run-up before it goes tight, which means a bigger jolt for both of you. Longer is better for open spaces and essential for hands-free wear — and for genuine distance work you want a long line rather than a longer walking lead.
Can one lead cover both Short and Medium?
Within its own range, yes — all our walking leads adjust through a three-glide buckle you can move one-handed. But no single lead covers 100 cm to 260 cm, which is why there are two options.
What is the difference between a Medium lead and a long line?
A Medium lead is for walking: up to 2.6 m, held in the hand or worn across the body. A long line is 5 to 15 m and is for recall training in open space — you stand still and your dog ranges. They are different jobs, not different sizes of the same thing.
My dog is between two sizes. Which do I pick?
The larger one. The extra weight is marginal; being under-specified is not.