WELCOME TO OUR Size of screws PROJECT

To promote your business on this page, click here to find out more!

Summary: The different sizes of screws and the conversion from metric to imperial sizes.

<< Back to projects

Screw sizes are a mystery to most people so we have tried to make life a little easier with the table below. A wood screw is sized by two different numbers. First is the diameter of the screw. The lager Phillips Head the number, the larger the diameter. A number 4 screw is much smaller than a number 12 screw. The length is given next and it should be remembered that the length given for a screw is the length that is buried in the wood or other material, it does not onclude the head of raised, or domed headed screws.

Slotted screws are fast becoming history and cross head screws are now the fashion but it must be remembered that a cross head screw can either be a Philips screw (Top image)or a Pozidrive Head

pozidrive/supadrive screw. They both require a different driver which can be found below.

See also our project on different types of screw and Countersinking. Pilot holes should also be used when insering screws.

Metric/Imperial Conversion Chart
Gauge mm	Length mm	Imperial Size	Gauge mm	Length mm	Imperial Size
3	12	4 x 1/2	3.5	12	6 x 1/2
	16	4 x 5/8		16	6 x 5/8
	20	4 x 3/4		20	6 x 3/4
	25	4 x 1		25	6 x 1
	30	4 x 1 1/4		30	6 x 1 1/4
	40	4 x 1 1/2		40	6 x 1 1/2
4	12	8 x 1/2	4.5	25	9 x 1
	16	8 x 5/8		30	9 x 1 1/4
	20	8 x 3/4		35	9 x 1 3/8
	25	8 x 1		40	9 x 1 1/2
	30	8 x 1 1/4		45	9 x 1 3/4
	35	8 x 1 3/8		50	9 x 2
	40	8 x 1 1/2		60	9 x 2 3/8
	45	8 x 1 3/4		70	9 x 2 3/4
	50	8 x 2		75	9 x 3
	60	8 x 2 3/8
	70	8 x 2 3/4
5	25	10 x 1	6	30	12 x 1 1/4
	30	10 x 1 1/4		40	12 x 1 1/2
	35	10 x 1 3/8		50	12 x 2
	40	10 x 1 1/2		60	12 x 2 3/8
	45	10 x 1 3/4		70	12 x 2 3/4
	50	10 x 2		75	12 x 3
	60	10 x 2 3/8		80	12 x 3 1/4
	70	10 x 2 3/4		90	12 x 3 1/2
	75	10 x 3		100	12 x 4
	80	10 x 3 1/4		110	12 x 4 3/8
	90	10 x 3 1/2		130	12 x 5 1/8
	100	10 x 4		150	12 x 6

Top Tools

Click on a tool below for additional information.

AEG BS14X Drill Driver 14.4V	All-Purpose Screwdriver Bit Set 100Pc	DeWalt Extreme 2 HSS Drill Set 13 Pc	Forge Steel Phillips Screwdriver No.4 200mm
Forge Steel Pozi/Pro Screwdriver No.1 100mm	Ryobi CSD-480CL 4.8V Screwdriver

Much more construction information is available in our bookstore. All the tools and fittings you need in the toolstore.

Forums

Fixing to walls problems
	-> Fixing to walls problems

Topics		Replies	Author	Views	Last Post
	Exterior pebbledash walls - painting or coating?	1	dodo	69	eddieman
	Fixing things to walls made of straw	3	oldcatton	286	plumbbob
	Fixing to hollow walls with metal studs	1	Louise28	204	gardnico1
	Metal RediDrivas	1	nisbet21	256	kbrownie
	What to do if a drilled hole goes wrong but you can't resite	3	dodo	715	kbrownie
	Drilling into a steel lintel?	1	jonti35	377	kbrownie
	Shelves on plasterboard walls	1	ewanandma	602	gardnico1
	Attaching a cable to skirting/wall invisibly and harmlessly?	1	simonlove	337	welsh bri
	Can't remove light fitting to replace bulb PLEASE HELP!!!!	4	spincat	1940	Mermaid
	bathroom accessories problem	1	notveryha	267	DUDE DIY
	Fixing round timber post to garage wall	1	dg_walter	276	welsh bri
	garage door gap!!	1	rlstandar	303	welsh bri
	Fixing Heavy Radiator to recently skimmed very old walls.	1	lynn	388	Freeman
	how to remove a screw that won't turn	2	ZenaJoh20	788	ZenaJoh20
	fixing swing bracket lcd tv 37 inches to plasterboard wall	0	kazyjacko	774	kazyjacko
	Fixing a deep 15" hole in wall	0	hapless	358	hapless
	Wall units on damp proof membrane	0	Bob63	309	Bob63
	Wall fixings	2	BRGRINCH	1627	BRGRINCH
	Exterior tile hung wall - but how do we fix the downpipes?	0	essdee	322	essdee
	Please help m with putting another pole in bulit-in wardrobe	0	littlewee	255	littlewee
	Fixing Plasterboard, Battens and Insulation to brick	0	LeSteve12	598	LeSteve12
	Fixing plinths to kitchen wall units	1	nanciebro	354	plumbbob
	Drill keeps unscrewing itself	2	Bearcub	666	Bearcub
	Dunelm mills blackout blinds	0	spitty	562	spitty
	Dry Wall painting	0	billboud	412	billboud
	Girl with fallen down curtain rail!!! Help!	4	distresse	1402	distresse
	fixing wardrobe to plaster bpard wall	1	chaste	546	thedoctor
	Fixing an uplighter	0	jaymac25	403	jaymac25
	Fixing run of kitchen wall cabinets to plasterboard wall	2	Boo	1398	plumbbob
	Plasterboard fixings hell	2	Rowan	1857	chris_on_
	ROLLER BLINDS CUT DOWN TO SIZE?	2	hobbit	1077	ALDA
	Fixing Shelves to Plasterboard Walls	1	gearyt	1766	Joiner_Mi
	FIXING INTO PLASTERBOARD	1	MUFFIN	1923	Joiner_Mi
	Fixing curtain rails to old walls	1	Carlos_dp	1358	ALDA
	obo nails	2	luckydog	968	chris_on_
	fixing to a very uneven surface	3	system_sh	1789	RJM
	fixing swivel towel rail to a stud wall	1	notrom	1263	welsh bri
	How to fix holes in internal brick wall?	1	sherbolto	1883	welsh bri
	Fixing dart board to a door	1	vezco	838	welsh bri
	Old cast iron air ventilation grille?	1	prbaxter	905	welsh bri
	Fixing Laminate Wall Cladding to a Plasterboard Wall	1	JamieFran	952	welsh bri
	wall plugs in to wood? or just plain old wood screws?	1	prbaxter	1072	ALDA
	Sparking drill?	3	andy2510	2286	chris_on_
	B@ggeration. Anchor screw rescue required!!	1	Heeber	1037	chris_on_
	plasterboard fixings only for a tv mount?	1	stepper	2149	chris_on_
	Query on fixing invisible shelves to wall	1	justinh	1401	chris_on_
	14Kg into plasterboard - no stud	1	jwilson	2052	chris_on_
	Fixing Kitchen wall cupboards to Plasterboard??????	1	cjm1973	2877	BonnieDog
	KITCHEN WALL CABINETS	2	ANDY777	1715	ALDA
	DIY Doctor Competition.......Click Here	0	gardnico1	596	gardnico1
Display topics from previous:

	-> Fixing to walls problems

Jump to: