What Is a Planer, and How Does It Differ From a Jointer?

A planer takes a board that is already reasonably flat and reduces it to a consistent thickness from end to end. A jointer takes a board that is warped, twisted or has an uneven edge and flattens one face or edge so it can sit true against a fence or another board. They solve different problems, and neither one does the other’s job well.

What does a planer actually do?

A planer feeds a board through a set of rollers and past a rotating cutterhead mounted above the bed, shaving a thin, even layer off the top face as it passes. The result is a board that is the same thickness all the way along its length, with two faces that are parallel to each other.

What a planer cannot do is fix a board that is bowed, cupped or twisted. If you feed a warped board through a planer, the rollers will flex it flat while it’s being cut, and the moment it comes out the other side and springs back, it’s still warped — just now thinner and warped. A planer only copies whatever shape the underside of the board already has; it doesn’t correct it.

This is why planers are sometimes called thickness planers, to separate them clearly from a hand plane or a jointer. If you want the background on how rotating cutters and feed mechanisms behave in general, the tool guide hub covers the underlying mechanics that show up across a lot of woodworking machinery.

What does a jointer do that a planer can’t?

A jointer flattens a face or squares an edge by referencing the board against a flat bed and fence, rather than against the board’s own opposite face. This is the step that removes twist, cup and bow, and it’s the step that makes an edge truly square to a face so two boards can be glued together without a visible gap.

A jointer has two flat tables — an infeed table and an outfeed table — set at slightly different heights, with a cutterhead in between. The board rides across the infeed table, gets a flat pass taken off the underside as it crosses the cutterhead, and then rides along the outfeed table, which is set to the height of the freshly cut surface. That relationship between the two table heights is what actually produces flatness; it’s not something a planer’s roller-fed design can replicate.

A jointer cannot control thickness along a board’s length the way a planer does. It flattens one reference surface at a time and doesn’t care what the opposite face looks like when it’s finished.

Planer vs jointer: what’s the real difference in one sentence?

A jointer creates a flat reference surface from a board that isn’t flat; a planer then uses that reference to cut the rest of the board to a uniform thickness. One establishes true, the other duplicates it.

Woodworkers often use the two machines in sequence: joint one face flat, then run the board through the planer with that flat face down against the bed, so the planer has something true to work from. Skip the jointing step on a badly warped board and the planer will simply produce a thin, consistent copy of the warp.

Do you need both a planer and a jointer in a home workshop?

It depends on what kind of timber comes into the shop. Rough-sawn lumber straight from a sawmill is rarely flat, so it usually needs a jointer pass before a planer pass makes any sense. Pre-surfaced boards from a lumberyard are often flat enough already that a planer alone, used carefully, gets a project moving.

Some smaller shops manage without a full-size jointer by using an alternative method to flatten a face — a router mounted in a sled that rides over the board, or careful use of a hand plane — and then rely on the thickness planer for the rest. That’s a legitimate workaround for occasional use, though it’s slower than a dedicated jointer for anyone working with rough stock regularly.

Straightedge laid across a board face to check flatness, the kind of test a jointer is used to correct — illustrating What Is a Planer, and How Does It Differ From a Jointer?

For a broader look at how tools in a given category typically differ in capability rather than just price, the comparisons archive has other head-to-head breakdowns worth reading alongside this one.

What safety issues come with planers and jointers?

Both machines run an exposed or partially guarded cutterhead spinning fast enough to remove wood on contact, and both throw wood chips and dust continuously while running. Eye protection is necessary for the chips, and hearing protection is necessary because both machines produce sustained noise well above comfortable levels during normal use — not just during unusual moments.

Dust from planing and jointing is fine and produced in volume; a dust extractor connected to the machine’s port, plus a respirator rated for wood dust when extraction alone doesn’t keep up, is the sensible baseline rather than an optional extra. This matters more with hardwoods and with manufactured boards containing fine particulate, where airborne dust lingers longer than it does with softer species.

A jointer’s cutterhead sits between two tables at roughly hand height, which is exactly why the guard over it and the push blocks or push sticks that come with the machine exist — they keep hands away from a spinning cutterhead without slowing the cut down. Planers can also react unpredictably if a board catches or stalls partway through the feed rollers, which is one of the reasons the general mechanics of sudden, forceful kickback are worth understanding before running any feed-driven machine; the article on what kickback actually is and what causes it explains the underlying forces even though it’s written with saws in mind. The safety and PPE section has more on matching protection to the specific hazard rather than treating “wear PPE” as a single blanket instruction.

What’s the difference between a benchtop and a stationary machine?

Benchtop planers and jointers are lighter, smaller, and sized to sit on a bench or stand rather than bolt to the floor. They’re aimed at boards of modest width and at occasional rather than daily use. Stationary versions have heavier cast tables, wider capacity, and more mass to resist vibration, which tends to show up as a smoother, more consistent cut on wider or longer stock.

Table width is the number that matters most when comparing jointers, since it sets the widest board you can flatten in one pass. For planers, the comparable figure is maximum board width and the range of thickness the machine can accept. Rather than treating either figure as a simple bigger-is-better spec, it’s worth thinking about the actual widths of the material a project realistically involves — a machine sized well beyond that just adds cost, weight and floor space without adding capability that gets used.

Motor power and cutterhead design affect how clean a cut looks and how the machine handles denser hardwoods, but the number on a spec sheet doesn’t translate directly into performance without knowing how it’s tested. The buying tools guide walks through how to read specifications like this without leaning on marketing numbers that don’t hold up in practice, and the buying guides archive has more detail specific to individual tool categories.

Does a planer replace a hand plane?

No — a hand plane is a manual tool guided entirely by the user’s own reference surface and technique, useful for small adjustments, fine-tuning a joint, or working on a piece too small or too delicate for a powered machine. A power planer removes material fast and evenly across a whole board but offers none of the fine control a hand plane gives for finishing work.

Many woodworkers keep both: a power planer and jointer for bulk stock preparation, and a hand plane for the final touches that a spinning cutterhead is too coarse a tool to manage.

Which one should be bought first?

For anyone starting with pre-surfaced lumber from a supplier, a planer is usually the more immediately useful purchase, since it turns boards of uneven thickness into consistent stock without needing a flattening step first. Anyone regularly buying rough-sawn timber will find a jointer becomes necessary fairly quickly, because skipping it means feeding warp straight through the planer and getting a thinner version of the same problem back out.

Neither machine is a substitute for the other, and buying one expecting it to cover both jobs is the most common mismatch new woodworkers run into. The power tools archive covers other machines in the same stationary-tool category, which is a useful place to compare how workshop equipment is specified and sized before deciding what a particular space and budget can realistically support.

Find Tool publishes general information, not professional advice. Power tools, mains electricity and workshop machinery are genuinely dangerous, and the safe settings, guards and procedures differ between models — always follow the manual and the markings on the tool in front of you rather than a general guide. Never remove or defeat a guard or safety feature. Anything involving fixed wiring, gas or structural work belongs to a qualified tradesperson. Wear the eye, ear and respiratory protection the task calls for.