Fit guide: how to know it fits

When you save your pet's measurements we tell you on every product whether it fits. But a collar and a dog sweater fit in completely different ways — so each product type is judged only on the measurements that actually decide its fit. Here is the whole rule, no small print.

The three measurements

Illustration of a dog with back length, chest girth and neck girth markedIllustration of a cat with back length, chest girth and neck girth marked
  • Back length — From the withers, where the collar sits, to the base of the tail on a standing animal. Decides how far a garment reaches.
  • Chest girth — Around the widest part of the ribcage, just behind the front legs. The most important measurement for harnesses and most clothing.
  • Neck girth — Around the neck where the collar sits, with two fingers under the tape.

What the labels mean

Fits

Every measurement relevant to the product type has been checked and the item is at least as large as your pet.

May fit

The item is missing a relevant measurement. It may fit — check the numbers in the fit section on the product page.

How each product type is judged

Dog and cat clothing

Judged on: back length, chest girth, neck girth.

A garment should cover the body without pulling: the back decides the length, the chest how it closes and the neck that the opening sits comfortably. So all three measurements are needed for a green Fits.

Harnesses

Judged on: chest girth, neck girth.

A harness is carried by the ribcage — that is where the pull is taken up. Back length has no bearing on a harness, so it never counts, neither for nor against.

Collars

Judged on: neck girth.

A collar is judged on a single measurement. It must adjust so it sits around the neck with room for two fingers. Back length and chest girth are not even mentioned.

Leashes, beds, bowls, toys, carriers

Judged on: no body measurements.

These are not worn on the body, so they never get a fit verdict and your pet's measurements never filter them out. Use the product's own dimensions on the product page.

Try it with your pet's measurements

Work out the fit

Fill in the measurements you know. Each product type answers straight away whether it can be judged — and how many items fit right now.

  • ClothingEnter measurements

    Judged on: back length, chest girth, neck girth.

  • HarnessesEnter measurements

    Judged on: chest girth, neck girth.

  • CollarsEnter measurements

    Judged on: neck girth.

  • Leashes, beds, bowls, toysNo fit verdict

    no body measurement is used.

How to measure

  1. Let the animal stand upright and relaxed.
  2. Measure the back from withers to tail base.
  3. Measure the chest girth behind the front legs.
  4. Measure the neck with two fingers under the tape.

Frequently asked questions

What does "Fits" mean on a product?
That the item is at least as large as your pet's measurements in every measurement relevant to that product type — and that the maker actually states. The item may be roomier, never smaller.
What does "May fit" mean?
That the item states no value for at least one measurement relevant to its type. It may well fit — but we cannot confirm it, so we don't promise it either.
Why doesn't a collar care about back length?
Each product type is judged only on the measurements that decide its fit. A collar sits around the neck, a harness around the chest. Back length affects neither, so it counts neither for nor against.
What if my pet is between two sizes?
Choose the larger one. The tolerance is one-sided — an item slightly larger counts as a fit, one that is smaller never does. And returns are always free, so a misjudged size costs you nothing.
SpringButiken

Second-hand dog and cat gear, measured in centimetres. Every item is one of one.

Subscribe to our newsletter – get 10% off via email!

Exclusive offers and news delivered straight to your inbox.

Free shipping over 90 € · Quality Guarantee · 14-day returns · Sustainable Choice

VisaMastercardKlarnaApple PayGoogle PayLinkPayPal

© 2026 SpringButiken