Number Bonds Worksheets - Printable Practice to 10 and 20

Number bonds are one of the foundations of early arithmetic: every number can be split into two parts, and knowing those part-part-whole relationships by heart is what lets children add and subtract fluently instead of counting on their fingers. This generator produces printable number bond worksheets in seconds, so parents and teachers can give students exactly the practice they need without buying workbooks or searching for PDFs. Choose a target sum to match the stage your child is at. Bonds to 5 suit the very beginning of kindergarten, bonds to 10 are the core skill of the first school year and the basis of the make-ten addition strategy, bonds to 20 extend the same idea across the teens, and bonds to 100 (usually practised with multiples and near-multiples of ten) support mental addition and subtraction in later grades. Then pick a problem style: missing part shows the whole and one part so the student finds what completes the bond, missing whole shows both parts so the student adds them, and mixed shuffles the two on one sheet so children must read each problem instead of applying one rule mechanically. Two representations are available. The circles layout prints the classic bond diagram — a whole circle joined by two branches to two part circles — which mirrors how number bonds are drawn in Singapore-math-style curricula and most primary classrooms. The equations layout writes each bond as a fill-in-the-blank number sentence instead, which bridges naturally into formal addition and subtraction notation. Both layouts leave generous space for pencil answers. Worksheets are reproducible: problems are drawn from a seeded random generator, so the same seed and settings always recreate the identical sheet. That makes it easy to reprint a page or give the same assessment to a whole class, while the new-version button advances the seed to produce a fresh set, and the Seed from RANDOM.ORG button fetches one true-random seed derived from atmospheric radio noise when you want a genuinely unpredictable worksheet. The answer key toggle adds a compact list of completed bonds at the bottom of the page, so you can print a grading copy for yourself and a clean copy for the student. Printing is one click. The controls and explanatory text are hidden and only the worksheet is sent to the printer, laid out to fit a single sheet of A4 or US Letter paper. Everything runs locally in your browser — nothing is uploaded, nothing is stored, and there is no limit on how many sheets you can make.