ᐅ Are the Kallax dimensions different from those in the instructions – is this normal?

Hello everyone,

I recently assembled my IKEA Kallax shelf and noticed that the dimensions of the individual compartments listed in the instructions do not exactly match the actual measurements of my unit. Specifically, the compartment sizes given in the instructions are slightly smaller than they really are.

My question is: Is it common for furniture like the Kallax to have actual external and internal dimensions that differ from those stated in the instructions? Or could I have received a defective part or made a mistake during assembly?

I have checked the instructions several times and also reviewed the information on the IKEA website, but I haven’t found an explanation. I’m mainly interested in whether such variations are typical for this series (e.g., due to manufacturing tolerances) or if adjustments might be necessary.

Thanks for your insights!

xenondan schrieb:
that the dimensions of the individual shelves in the instructions do not exactly match the actual dimensions of my item.

Hey, that’s actually quite common! IKEA often has small manufacturing tolerances – especially with wood modules, it can easily be off by 2-3 mm (0.08–0.12 inches). This doesn’t mean your furniture is damaged or defective.

Sometimes the measurements are more like “net values,” meaning the design dimensions rather than the precise outer measurements. If you can fit everyday items inside and everything feels stable, I wouldn’t worry about it.

But of course, if there are really large differences, that would be a different matter. Usually, IKEA will send a replacement then. So just measure carefully and note anything unusual. 🙂

xenondan schrieb:
Or did I possibly receive a faulty part or make a mistake during assembly?

Regarding deviations in Kallax: There are indeed manufacturing tolerances that can affect individual parts by about ±2 mm (±0.08 inches). From a technical perspective, this is completely normal and accounted for in the design allowances during assembly.

However, it is important to check the following details:

1. Extent of deviation: How much larger are the compartments compared to the instructions?
2. Type of measurements: Are you comparing external dimensions, internal dimensions, or load capacity measurements?
3. Assembly: Were all connecting elements properly tightened and securely in place, since incorrect assembly can cause apparent dimensional differences.

I recommend making a precise sketch of your measured dimensions and checking whether the deviation is consistent across all compartments or only on individual ones.

If you want, provide a specific measurement, and I can tell you whether the deviation is within the usual range or not. Sometimes there are updates to the assembly instructions that do not fully correspond to the delivered parts, so careful measuring is helpful.

leteo schrieb:
IKEA often has small manufacturing tolerances

That is generally true, but I like to question it: There are clear standards for furniture dimensions and manufacturing processes, especially for mass-produced furniture like the Kallax.

Deviations are possible, but if, for example, the shelf compartment dimensions are significantly larger than stated, this could indicate a design or manufacturing defect.

I would ask you to specify exactly how large the deviations are. Also, have you checked whether different versions or production batches might result in different measurements? It is not unlikely that there was a revision that does not match the older instructions.

Additionally, you should clarify whether you might be confusing internal dimensions with external dimensions – this very often leads to such misunderstandings.

xenondan schrieb:
Is it normal for furniture like the Kallax to have actual external and internal dimensions that differ from the measurements given in the instructions?

I agree with the previous comments – the Kallax is typically manufactured with certain tolerances. These are often around ±2 mm, as engineered wood products can slightly expand or contract depending on humidity and storage conditions.

It’s important to understand that the dimensions in the instructions usually refer to internal or fitting measurements for accessories, which can be influenced by edges and supports. Therefore, the overall cabinet dimensions may differ slightly.

However, if you notice deviations greater than 5 mm or inconsistent measurements between identical parts, I would recommend contacting IKEA – you might want to report a quality issue or request an exchange.

What exactly did you measure? Which dimensions (e.g., width x height x depth of the compartments) and how much do they differ from the instructions? Feel free to share more details so it can be assessed better!