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Choosing between 80-grit and 120-grit sandpaper depends on how much finish must come off and how smooth the wood needs to be afterward. For most refinishing jobs, 80 grit is the faster cutting abrasive, while 120 grit is the safer choice when the finish is thin, the wood is soft, or you are close to bare wood. Neither grit is automatically “better.” The wrong choice can leave deep scratches, remove too much material, or make the job take far longer than necessary.
What the Grit Numbers Mean
Grit refers roughly to the size of the abrasive particles on the paper. Lower numbers use larger, more aggressive particles. As the number rises, the abrasive removes less material but leaves a finer scratch pattern.
In practical terms, 80 grit is a stripping and shaping abrasive. It can cut through many clear finishes, paint films, and uneven areas quickly. 120 grit is a medium abrasive used for refining scratches, smoothing bare wood, and preparing a surface for many stains and paints.
Grit ratings are not perfectly identical between every manufacturer, especially between different abrasive standards. Still, the general difference is consistent: 80 grit cuts faster and scratches deeper; 120 grit cuts slower and leaves a more manageable surface.
When 80-Grit Sandpaper Makes Sense
Use 80 grit when the existing finish is thick, hard, damaged, or difficult to remove with finer paper. It is useful on heavily varnished tabletops, painted furniture, floors, doors, and wood with multiple old finish layers. An 80-grit disc on a random-orbit sander can remove finish far faster than 120 grit.
It is also the better starting point when the surface has deep scratches, raised grain, water damage, or uneven repairs that must be leveled. On a flat surface, 80 grit can remove material predictably as long as you keep the sander moving.
The main risk is over-sanding. A power sander with 80 grit can create a shallow dish, round over an edge, or cut through a thin veneer in seconds. It can also leave scratches deep enough that 120 grit alone will not remove them. On veneer, plywood faces, soft pine, and profiled trim, consider starting with a 120-grit sanding discs or stripping chemically before sanding.
When 120-Grit Sandpaper Is the Better Starting Point
Choose 120 grit when the finish is already thin, partly worn, or easy to remove. It works well for scuffing a sound finish before repainting, removing the last traces of a stripper, and smoothing bare wood after 80 grit has done the heavy work.
120 grit is also a good starting point for hardwoods such as oak, maple, ash, and cherry when you want to avoid unnecessarily deep scratches. It is less likely than 80 grit to tear the surface or remove important detail from a routed edge. For softwoods, however, even 120 grit can leave dents and uneven areas if you press down or sand in one spot.
Do not assume 120 grit will remove every finish efficiently. Thick polyurethane, floor varnish, catalyzed coatings, and old paint can quickly clog medium-grit paper. If the paper stops cutting and begins polishing the finish, replace it or move down to 80 grit.
80 Grit vs. 120 Grit at a Glance
| Factor | 80 grit | 120 grit |
|---|---|---|
| Finish removal speed | Fast on thick or hard coatings | Slow to moderate |
| Scratch depth | Deep and noticeable | Finer and easier to remove |
| Risk to veneer and edges | High | Moderate |
| Typical use | Initial stripping and leveling | Refining bare wood and light scuffing |
| Best next step | 120, then 150 or finer | 150 or 180, depending on the finish |
The Best Sanding Sequence
For a thick finish on solid wood, start with 80 grit only where necessary. Once the coating is removed, switch to 120 grit to erase the 80-grit scratches. If the final surface will be stained, continue to 150 or 180 grit unless the stain manufacturer recommends otherwise. Many woods accept stain more evenly at 150 grit than at 80 or 120.
A practical sequence is 80, 120, and 150 grit. On open-grained hardwood or a surface that will receive paint, 120 followed by 150 or 180 may be enough. Do not skip directly from 80 to 180 unless you have tested the surface carefully; the finer paper may polish the tops of the scratches while leaving the deeper grooves visible.
For sanding by hand, use a assorted-grit wood sandpaper pack so you can change grits instead of forcing one sheet to do every job.
How to Avoid Sanding Damage
Test your chosen grit in an inconspicuous area first. Sand a patch about 4 inches square for 10 to 15 seconds, then wipe away dust. If 120 grit is barely changing the finish, step down to 80. If 80 grit exposes a different-colored layer immediately, stop and confirm whether you are working through veneer, stain, or the actual wood.
Keep a random-orbit sander flat and moving slowly, generally around 1 to 2 inches per second. Do not press hard; the tool’s weight should provide most of the pressure. On edges, use a sanding block or sand by hand. Power sanding directly over an edge can round it in one pass.
Replace paper when the abrasive is shiny, clogged, or no longer produces fresh dust. Clogged paper creates heat and friction rather than efficient cutting. Vacuum between grits instead of wiping aggressively with a dirty rag, since leftover coarse particles can create new scratches.
When Sanding Is Not the Best Removal Method
If the finish is very thick, gummy, or painted, chemical stripping can remove most of it while preserving more wood. This is especially helpful on carvings, moldings, veneer, and furniture with many contours. After stripping, let the wood dry completely, scrape away residue, and use 120 grit to clean and smooth the surface.
For large floors or broad boards, a floor sander may be appropriate, but 80 grit can remove significant material quickly. Rent the machine only if you can control it and have a plan for edging and subsequent grits. For small furniture projects, a random-orbit sander for woodworking is usually easier to manage.
What to Buy
If you are buying only one grit, 120 grit is the more versatile and forgiving option for light refinishing, paint preparation, and final smoothing. If the project has multiple heavy finish layers, buy both 80- and 120-grit paper. The cheaper option is fine for hand sanding and occasional work, provided the sheets stay flat and the abrasive does not shed prematurely. For power sanders, better-quality discs can be worth the extra cost because they cut longer, clog less, and attach more reliably.
Use 80 grit to remove stubborn finish, then stop using it as soon as the coating is gone. Use 120 grit to refine the surface and prepare it for the next finishing step. That simple division gives you speed without leaving scratches that become visible under stain, paint, or clear coat.
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