The short answer
A standard 80″ interior door takes three 3-1/2″ × 3-1/2″ hinges. Match the corner of the hinge to the mortise in the door and jamb: 5/8″ radius, 1/4″ radius or square. Prehung doors arrive with the hinges set, so you only order hinges for slabs and site-built frames.
Size and count
| Door | Hinges |
|---|---|
| Standard 80″ interior, hollow core | Three 3-1/2″ × 3-1/2″ |
| Standard 80″ interior, solid core | Three 3-1/2″, with screws long enough to reach the framing |
| Taller or heavier than standard | More or larger hinges; we confirm on the quote |
| Exterior doors | Usually 4″ hinges. Not covered here |
Match the corner
Hinge mortises are routed with a rounded or square corner, and the hinge has to match or it won’t sit flush.
- 5/8″ radius: about the curve of a quarter. Common on residential doors.
- 1/4″ radius: about the curve of a dime.
- Square: no curve. Usually hand-cut or older mortises.
Hold a quarter or a dime in the corner of the mortise. Whichever matches the curve tells you the radius.
Hinge types
| Type | What it does | Use it for |
|---|---|---|
| Residential butt, radius corner | The standard hinge, set into routed mortises | Most swing doors |
| Flush (butterfly) | One leaf nests in the other, so no mortise is needed | Light closet doors and quick site work |
| Lift-off | The door lifts off the pin without unscrewing the leaves | Doors that come off for moves or painting |
Finish and ordering
- Match the handles. Order hinges in the same finish as the levers, so a satin nickel suite has satin nickel hinges.
- Prehung saves the work. Prehung doors come hinged in the jamb. See prehung vs slab doors.
- Heavy doors. On solid core doors, use at least one long screw per hinge into the stud so the door doesn’t sag. See solid core vs hollow core.
Sources
Code requirements change and local rules vary. Confirm sizes and clearances with your designer and building department before ordering. We supply doors, trim and hardware; we’re not a code consultant.
