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Q: “What diameter hole is used on 3-hole punches for use in a 3-ring binder?”
A: While there is no true ‘industry standard’, the majority of 3-hole punches use a 5/16” diameter hole for use in standard 3-ring binders. While some manufacturers offer punches with a smaller holes like 1/4” or even 9/32”, the vast majority use 5/16”.
If you’re trying to match a particular hole pattern, be sure to use our handy Drill Bit Identification Guide. You can print out this handy PDF to identify round hole diameters for most paper drill bits as well as the bit style/manufacturer.
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