A squeaky, sagging door almost always comes down to a $6 part most people never think about. Interior door hinges carry the entire weight of the door, control how it swings, and quietly set the tone of a room through their finish. Pick the wrong size or the wrong number and you get doors that drag, latches that miss, and gaps that let light spill through. This guide explains the sizes, types, and finishes so you buy exactly what your doors need the first time.
Part of our Windows & Doors guide — explore the full guide →
- Anatomy of a Door Hinge
- Standard Sizes and How Many You Need
- Hinge Types Beyond the Basic Butt
- Finishes That Coordinate Your Home
- How to Measure Before You Buy
- Replacing a Hinge the Right Way
- Fixing Common Hinge Problems
- Decorative and Specialty Hinge Options
- How Many Hinges for Different Door Types
- Signs Your Hinges Need Replacing
- Choosing the Right Hinge for Your Door
Anatomy of a Door Hinge
A butt hinge, the type on nearly every interior door, has two leaves joined by a knuckle and a pin. One leaf mortises into the door edge, the other into the jamb. The pin lets the door swing, and on many hinges you can tap it out to remove the door without unscrewing anything.
The small details matter. Corners come either square or radius, meaning slightly rounded. Most machine-cut modern jambs use a 5/8-inch radius corner, while older homes with hand-chiseled mortises usually take square-corner hinges. Matching the corner type saves you from re-cutting mortises.
Standard Sizes and How Many You Need
Interior residential doors overwhelmingly use a 3.5-inch hinge, measured by the height of the leaf. Taller or heavier doors step up to 4-inch or 4.5-inch hinges. A quick rule for hinge count:
- Doors up to 60 inches tall: two hinges
- Doors 60 to 90 inches tall: three hinges
- Doors over 90 inches or solid-core slabs: four hinges
Most standard 80-inch interior doors get three 3.5-inch hinges. A heavy solid-core door benefits from a fourth hinge or a jump to 4-inch to prevent long-term sag.
Hinge Types Beyond the Basic Butt
Ball-Bearing Hinges
Ball-bearing hinges have small bearings in the knuckle that reduce friction and wear. They are the right call for heavy solid-core doors and high-traffic doors that swing dozens of times a day, because they resist squeaking and sagging far longer than plain hinges.
Spring Hinges
Spring-loaded hinges pull a door closed on their own. They are common where code or convenience calls for self-closing doors, such as an attached-garage passage door, and the tension is adjustable with a hex key.
Non-Mortise and Concealed Hinges
Non-mortise hinges mount on the surface without chiseling, handy for lightweight closet and cabinet-style doors. Fully concealed European hinges hide completely when the door is shut, giving a clean, modern look on frameless interior and closet doors.
Finishes That Coordinate Your Home
Hinges are hardware, so match them to your doorknobs, hinges, and other trim for a cohesive look. Satin nickel and brushed nickel are the most popular neutral choices. Oil-rubbed bronze suits traditional and farmhouse interiors, while matte black has surged in modern and transitional homes.
Do not mix finishes on the same door. If your knob is matte black, the hinges should be matte black too. Coordinating hardware across a room reads as intentional and quietly raises the perceived quality of the whole space.
How to Measure Before You Buy
Pull one existing hinge and measure the leaf height and width with it fully open. Note the corner style, square or radius, and the radius size if rounded. Check the screw hole pattern so new hinges line up with existing holes, which saves you from filling and re-drilling.
Count the total hinges on the door, and buy all of them at once from the same product line so the finish and knuckle style match perfectly. Buying one-off replacements almost always leaves you with a slightly different tone.
Replacing a Hinge the Right Way
You can swap hinges without removing the door if you work one hinge at a time. Open the door, place a shim or wedge under the outer bottom corner to support the weight, and unscrew only the top hinge first.
- Remove the screws from one hinge leaf on the jamb, then the door
- Set the new hinge in the existing mortise and start all screws by hand
- Tighten fully, then move to the next hinge and repeat
- Test the swing and latch before removing the support wedge
Doing one hinge at a time keeps the door aligned and the mortises registered, so the door hangs true when you finish.
Fixing Common Hinge Problems
A squeak means dry metal. Tap the pin halfway out, wipe it, add a drop of lithium grease or even a bit of petroleum jelly, and tap it back. Avoid thin oils that run and attract dust.
A sagging door that scrapes the frame usually has loose top-hinge screws. Tighten them, and if the holes are stripped, replace one short screw with a 3-inch screw that reaches into the wall framing behind the jamb. That single long screw pulls the door back into alignment and is the pro’s go-to fix for a drooping door.
Decorative and Specialty Hinge Options
Beyond function, hinges can be a design detail. Decorative tips, the small finials that cap the knuckle, come in ball, steeple, and urn styles that add a subtle traditional flourish to a formal room. On visible hinges in an entryway or a study, these small touches read as custom.
For period homes, reproduction hinges in aged brass or hand-forged iron match the era’s character. In modern builds, some homeowners choose fully concealed hinges so the door appears to float with no visible hardware at all. If you want a door to swing both directions, such as a butler’s pantry passage, double-action gravity hinges let it push open from either side and self-center closed. Match any specialty choice to the room’s overall style so it feels deliberate rather than out of place.
How Many Hinges for Different Door Types
Door weight and construction should guide your hinge count and grade, not just height. Hollow-core doors, the lightweight standard in many homes, are fine with two or three plain hinges. Solid-core and solid-wood doors weigh far more and demand three or four hinges, ideally ball-bearing, to carry the load without sagging over the years.
- Standard 80-inch hollow-core door: three 3.5-inch plain hinges
- Solid-core 80-inch door: three or four 3.5- or 4-inch ball-bearing hinges
- Tall 8-foot or oversized doors: four hinges, stepping up to 4.5-inch
- Heavy exterior-grade or barn-style slabs: four heavy-duty hinges minimum
When in doubt, add one more hinge than the minimum. The extra hinge distributes the weight, reduces strain on each mortise, and keeps the door hanging true for the life of the home.
Signs Your Hinges Need Replacing
Hinges give clear warnings before they fail. A persistent squeak that returns even after lubrication means the pin or knuckle is worn. Visible rust, pitting, or a paint-clogged mechanism signals it is time for fresh hardware. If the door will not stay open or drifts on its own, a hinge is out of alignment or the leaves are bent.
A door that binds at the top or scrapes the frame despite tightening screws often has a worn or damaged hinge that no longer holds the correct geometry. Replacing worn hinges is cheap insurance against a bigger problem, and since the mortises are already cut, a swap takes only a few minutes per hinge.
Choosing the Right Hinge for Your Door
Match the size to your door height and weight, the corner style to your existing mortise, and the finish to your other hardware. For everyday hollow-core doors, standard 3.5-inch plain-bearing hinges are fine. For solid-core, heavy, or high-traffic doors, spend a few extra dollars on ball-bearing hinges.
Getting interior door hinges right is a small, cheap detail that pays off every single day in doors that swing smoothly, latch cleanly, and look put-together. Measure carefully, match your finishes, and use that one long screw when things start to sag.
