Dry sanding old paint without testing for lead Fine grit on thick paint — it loads instantly and polishes rather than cuts Heat guns near eaves, cavities and old insulation, where smouldering can start

Which sandpaper grit removes paint?

40 to 80 grit open-coat aluminium oxide or ceramic — but test for lead paint before sanding anything painted before the 1990s.

Paint clogs abrasive far faster than wood does, because the coating softens under friction and rolls into balls that fill the grain of the sheet. Open-coat papers, where the abrasive covers only part of the backing, are made specifically for this, and lower speeds and lighter pressure produce less heat and less loading. The safety point overrides all of it: lead was in domestic paint until 1978 in the US and, in decorative paints, into the early 1990s in the UK, and dry sanding turns it into fine dust that settles through a house and is particularly harmful to children. Test kits are cheap. Where lead is present, sanding is the wrong method entirely and chemical stripping, wet methods or professional removal is the answer.

The options, ranked

Ranked best-first for the stated job. The third column is why the others exist.
Option	Good at	Bad at
40-60 grit open coat	Cuts through thick layered paint fast without clogging, because the open coat leaves space for the swarf.	Leaves deep scratches that need working out through several finer grits.
80 grit	A reasonable compromise on a single thin coat, removing paint without gouging the substrate.	Clogs quickly on soft or fresh paint.
Ceramic abrasive	Self-fracturing grains stay sharp far longer, so it lasts several times as long on paint.	Costs more per sheet, though usually less per job.
Chemical stripper or a heat gun	Removes paint without generating dust, which is the only safe option where lead is present.	Slow and messy; heat guns can scorch timber and ignite debris in cavities.

Technique that changes the outcome

Test for lead before touching pre-1990s paintwork
Use open-coat paper and let the abrasive cut rather than leaning on it
Work through 60 to 80 to 120 rather than trying to finish with the stripping grit
Vacuum with a HEPA extractor rather than sweeping

What goes wrong

Dry sanding old paint without testing for lead
Fine grit on thick paint — it loads instantly and polishes rather than cuts
Heat guns near eaves, cavities and old insulation, where smouldering can start

Compiled practical guidance rather than a published standard. Product formulations vary by brand and market, so read the label — and where the work is structural, electrical or gas, the regulations that apply where you are govern rather than anything here.

For	Use
Bare wood	80 to 120 to 150 on softwood, finishing at 180 or 220 on hardwood — and stop there, because over-sanding ruins stain.
Rusty metal	60 to 80 grit to strip scale, 120 to 180 to blend — then prime the same day, because bare steel flash rusts within hours.
Between coats	220 to 320 grit with almost no pressure — you are knocking off dust nibs, not removing the coat.
Plasterboard filler	120 to 150 grit to level joint compound and 220 for the final pass, ideally on a mesh with a vacuum attached.
Plastic	Start at 320-600 wet for scratches, work up to 2000, then finish with a plastic polish — and keep it cool.
Car body filler	80 grit to shape, 180 to refine, 320 before primer and 400-600 on the primer before paint.
Final finish	400 to 600 dry, or 800 to 2000 wet on a fully cured film, followed by a polishing compound.
Wet sanding	Silicon carbide wet-or-dry paper, water with a drop of detergent, a rigid block, and 800 grit upwards.

Common questions

Which sandpaper grit removes paint?: 40 to 80 grit open-coat aluminium oxide or ceramic — but test for lead paint before sanding anything painted before the 1990s.
What should I avoid?: Dry sanding old paint without testing for lead Fine grit on thick paint — it loads instantly and polishes rather than cuts Heat guns near eaves, cavities and old insulation, where smouldering can start

Which sandpaper grit for bare wood before finishing? 80 to 120 to 150 on softwood, finishing at 180 or 220 on hardwood — and stop there, because over-sanding ruins stain.
Which sandpaper grit removes rust? 60 to 80 grit to strip scale, 120 to 180 to blend — then prime the same day, because bare steel flash rusts within hours.
Which sandpaper grit between coats of paint or varnish? 220 to 320 grit with almost no pressure — you are knocking off dust nibs, not removing the coat.
Which sandpaper grit for plasterboard and filler? 120 to 150 grit to level joint compound and 220 for the final pass, ideally on a mesh with a vacuum attached.
Which sandpaper grit for plastic? Start at 320-600 wet for scratches, work up to 2000, then finish with a plastic polish — and keep it cool.
Which sandpaper grit for car body filler? 80 grit to shape, 180 to refine, 320 before primer and 400-600 on the primer before paint.
Which sandpaper grit for a final finish? 400 to 600 dry, or 800 to 2000 wet on a fully cured film, followed by a polishing compound.
Which sandpaper should I use for wet sanding? Silicon carbide wet-or-dry paper, water with a drop of detergent, a rigid block, and 800 grit upwards.

Sources

Typical range compiled from manufacturer specifications — At One Place

How these figures are compiled and checked