Label Roll Core Size Guide
Printer Compatibility Guide
Label Roll Core Size Guide
Choosing the correct label roll core size helps make sure your labels fit your printer and feed correctly. This guide explains the difference between 25mm, 38mm/40mm and 76mm cores, and how to choose the right roll before ordering.
Quick answer
The core size is the diameter of the cardboard tube inside the label roll. It is not the same as the label size. A roll can have the same label size, such as 100mm x 50mm, but be supplied on different core sizes depending on the printer.
What is a label roll core?
A label roll core is the cardboard tube in the centre of the roll. The printer or roll holder sits through this tube so the labels can unwind smoothly during printing.
The core size matters because every printer has limits on what roll it can hold. Some smaller desktop printers only fit compact rolls, while larger industrial printers often use bigger rolls with larger cores.
Small core
Common for compact desktop printers and smaller rolls that sit inside the printer.
Medium core
Used on some medium rolls and commercial label setups. Some products may say 38mm while customers may describe it as 40mm.
Large core
Common for larger rolls, industrial printers, external roll holders and high-volume printing.
Core size comparison table
| Core Size | Common Printer Type | Common Use | Main Benefit | Check Before Ordering |
|---|---|---|---|---|
| 25mm Core | Desktop label printers | Small rolls, barcode labels, address labels, courier labels | Compact roll size, often fits inside smaller printers | Printer internal roll space and maximum roll diameter |
| 38mm/40mm Core | Some desktop, commercial and light industrial printers | Medium rolls and regular business printing | More roll capacity than 25mm without moving to large industrial rolls | Whether your printer uses 38mm, 40mm or an external holder |
| 76mm Core | Industrial printers and external roll holders | Warehouse, logistics, freight, manufacturing and high-volume labels | Supports larger rolls and fewer roll changes | External holder size and maximum roll diameter |
Which core size should I choose?
- Check your existing label roll. If your current roll fits and prints correctly, match the same core size when reordering.
- Check your printer model. Printer specifications usually list the supported core size, roll width and maximum outside roll diameter.
- Check whether the roll sits inside or outside the printer. Smaller desktop printers often hold the roll internally, while larger setups may use an external roll holder.
- Check the label material. Direct thermal labels do not use a ribbon, while thermal transfer labels require a ribbon. Core size and print method are separate, but both must suit the printer.
- Ask before ordering. If you are not sure, send us your printer model or a photo of your current roll and we can help check the best option.
25mm core labels
A 25mm core is commonly used for smaller label rolls and compact desktop label printers. This option is useful when the roll needs to fit inside the printer body. It is often used for courier labels, barcode labels, product labels, address labels and general business labelling.
Choose a 25mm core when your printer is designed for compact rolls or when your existing roll has a small cardboard tube in the centre.
38mm/40mm core labels
A 38mm or 40mm core is a mid-size roll core. This size is useful for businesses that need more label capacity than a small desktop roll, but do not need a full industrial 76mm core roll.
Some product descriptions may list this as 38mm core, while customers may commonly call it 40mm core. Because printer requirements can be specific, it is still best to check your printer or existing roll before ordering.
76mm core labels
A 76mm core is commonly used for larger rolls, industrial printers and external roll holders. It is often chosen for higher-volume printing environments where businesses want more labels per roll and fewer roll changes.
This core size is often used in warehousing, freight, manufacturing, logistics and production settings.
Important: core size is not the same as label size
A label listed as 100mm x 50mm describes the size of each label. The core size describes the cardboard tube inside the roll. The same label size may be available on different core sizes depending on the printer and roll setup.
| Term | What it means | Example |
|---|---|---|
| Label size | The width and height of each individual label | 100mm x 50mm |
| Core size | The diameter of the cardboard tube inside the label roll | 25mm, 38mm/40mm or 76mm |
| Roll outside diameter | The full size of the roll from outside edge to outside edge | A larger roll may not fit inside a small printer |
Direct thermal vs thermal transfer labels
Core size tells you how the roll fits into the printer, but it does not tell you whether the label is direct thermal or thermal transfer.
Direct Thermal Labels
Direct thermal labels print using heat-sensitive material and do not require a ribbon. They are commonly used for shipping labels, courier labels, barcode labels and short to medium-term labelling.
Shop Direct Thermal LabelsThermal Transfer Labels
Thermal transfer labels use a printer ribbon to transfer print onto the label. They are often used when a longer-lasting or more durable print is required.
Shop Thermal Transfer LabelsShop by label need
Once you know your core size, choose the label type that suits your printer and application.
Frequently asked questions
Can I use any core size in my printer?
No. The core size must suit your printer or roll holder. The roll also needs to fit within the printer’s maximum roll width and outside diameter.
Is 38mm the same as 40mm?
Some customers refer to this mid-size core as 40mm, while some products may list it as 38mm. They are close in everyday wording, but you should still check your printer requirements before ordering.
Does core size affect print quality?
Core size mainly affects how the roll fits and feeds. Print quality is more affected by the printer, label material, ribbon, print settings and label type.
What should I send if I need help?
Send your printer model, the label size you need, and a photo of your current label roll if available. A photo of the cardboard tube inside the roll can help identify the core size.
Still unsure which core size you need?
Contact All Types Labels before ordering. We can help check the best label roll option based on your printer, current roll, label size and printing requirements.
Email: sales@alltypeslabels.com.au
Phone: 0413 872 096
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