How many 10 AWG wires fit in 1/2 inch EMT?

5 10 AWG THHN conductors fit in 1/2 inch EMT at the applicable fill percentage.

How many 10 AWG wires fit in 3/4 inch EMT?

10 conductors, using a nominal THHN outside diameter of 0.164 in and the 40% fill rule for three or more conductors.

Do neutrals and grounds count toward fill?

Yes, every conductor in the raceway counts for fill. Grounds are excluded only from the count of current-carrying conductors used for ampacity adjustment.

What is the cross-sectional area of 10 AWG THHN?

About 0.0211 square inches, from A = π × (OD / 2)² with a nominal insulated OD of 0.164 in.

10 AWG Conduit Fill by Conduit Size

How many 10 AWG THHN conductors fit in EMT, IMC, RMC and PVC conduit, 1/2 inch through 4 inch, with the 40% fill rule applied.

Quick answer

5 10 AWG THHN conductors fit in 1/2 inch EMT and 10 fit in 3/4 inch EMT, at 40% fill for three or more conductors. Each conductor consumes 0.0211 sq in from a nominal insulated outside diameter of 0.164 in. Neutrals and grounds count.

10 AWG conductors per conduit trade size

Same-size conductors only, at 53% for one, 31% for two and 40% for three or more.

Conduit	1/2"	3/4"	1"	1-1/4"	1-1/2"	2"	2-1/2"	3"	3-1/2"	4"
EMT	5	10	16	28	38	63	110	167	200	200
IMC	6	11	18	31	42	68	97	150	200	200
RMC	5	10	16	28	39	64	92	142	189	200
PVC Sch 40	5	9	15	27	37	62	88	137	184	200
PVC Sch 80	4	7	13	23	32	54	77	121	164	200

Published standard

Source & method: Counts are the largest whole number where n × conductor area stays inside the raceway area times the applicable fill percentage. Mix conductor sizes in the calculator.

Fill behaviour at 10 AWG: 3/4 inch becomes the working minimum

At 10 AWG the counts drop enough that 3/4 inch is the practical floor for anything beyond a single two-wire circuit with a ground. A 30 A water heater or dryer circuit fits 1/2 inch; add a second circuit and the raceway grows.

10 AWG is also frequently stranded, which pulls easier than solid at the same area but occupies the same nominal insulated diameter in the calculation. The table on this page uses nominal THHN outside diameter, so stranded and solid of the same size return the same count.

Source & method: Counts referenced above come from the computed table on this page — how these numbers are derived.

What each raceway type means

EMT — EMT (electrical metallic tubing)
IMC — IMC (intermediate metal conduit)
RMC — RMC (rigid metal conduit)
PVC Sch 40 — PVC Schedule 40
PVC Sch 80 — PVC Schedule 80

Full fill charts by raceway

Per-type counts for every trade size, plus the cross-type comparison and reverse lookup.

Frequently asked

How many 10 AWG wires fit in 1/2 inch EMT?: 5 10 AWG THHN conductors fit in 1/2 inch EMT at the applicable fill percentage.
How many 10 AWG wires fit in 3/4 inch EMT?: 10 conductors, using a nominal THHN outside diameter of 0.164 in and the 40% fill rule for three or more conductors.
Do neutrals and grounds count toward fill?: Yes, every conductor in the raceway counts for fill. Grounds are excluded only from the count of current-carrying conductors used for ampacity adjustment.
What is the cross-sectional area of 10 AWG THHN?: About 0.0211 square inches, from A = π × (OD / 2)² with a nominal insulated OD of 0.164 in.

Conduit fill for nearby sizes

Same 40% fill rule applied to the sizes either side of this one, wrapping around the range so every size is reachable.