Quick answer: the NIIMBOT B21 and B21 Pro all use the same gap-cut thermal label rolls, from 20 mm up to 50 mm wide. Any roll in our store marked “for B1 B2 B21” fits these printers. The most popular sizes are 40×20 mm, 40×30 mm, 50×30 mm and 40×60 mm, and because the printers are direct thermal, there is no ink to match — only the roll. But take note: some of the labels, like the photo label and the dual-colour label, are for the 300dpi Pro series only, like B1 Pro, B2 Pro and B21 Pro.
Common label sizes and what they are used for
- 40×20 mm — the everyday all-rounder: sauce bottles, storage boxes, product price stickers.
- 40×30 mm / 50×30 mm — pantry containers and product labels with room for a name, a date and a barcode.
- 40×60 mm and larger — shipping cartons, jars with full ingredient lists, retail shelf labels.
- Round 20–50 mm — jar lids, date dots, packaging seals and colour-coding.
- Cable tag rolls — flag-style labels that wrap around a wire and read from both sides.
Label materials you can choose
Size is only half the choice — the material decides where the label survives:
- White labels — waterproof and oil-proof, the workhorse for kitchens, offices and shops.
- Transparent labels — the print shows, the sticker disappears; ideal for glass canisters and branded packaging seals.
- Round stickers — date dots and colour codes.
- Freezer labels — stay put on batch-cooked meals below zero, where ordinary stickers curl off.
- Matte writable labels — take a handwritten note on top of the printed text.
- Price tag rolls — clean, legible rack and case pricing for shops and cafes.
On the Pro-series printers (B1 Pro, B2 Pro, B21 Pro) you also unlock photo label rolls — a picture from your camera roll printed as a sticker — and dual colour rolls for two-tone labels.
How to tell if a roll fits your printer
Check the product name: every refill in our store lists its compatible printers, so anything named “for B1 B2 B21” loads straight into a B21-series machine. Genuine NIIMBOT rolls are also recognised automatically by the printer, and the app fills in the correct label size for you — no manual calibration.
What about the D-series or wider printers?
Rolls are not interchangeable across series. The pocket-sized D11, D110, D101 and H1S take narrower 12–25 mm rolls from the D-series collection, while the B31 and B4 go up to 75 mm with their own wide-format rolls. If you own several NIIMBOT printers, buy by collection — each printer’s collection only shows rolls that fit.
Where to buy B21 labels in Singapore
Every size and material above ships from our Singapore warehouse island-wide — browse the full B1 & B21 label collection or the Pro-series collection. Not sure the B21 series is the right printer for you in the first place? See how a cafe and a boutique use theirs in our real-life scenarios.