IP21 vs IP40
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP21 and IP40 are both IEC 60529 ingress protection codes, but they differ in solid-object protection (level 2 vs 4) and liquid protection (level 1 vs 0). IP21 is rated for > 12.5 mm — finger and vertically dripping water, while IP40 provides > 1 mm — small wires and no protection.
Designed for environments requiring protection against solid objects larger than 12.5 mm and protection against vertically falling drops of water. Dripping water shall have no harmful effects., IP21 is an IEC 60529 code combining solid level 2 with liquid level 1.
IP40 protects against small tools and wires (1 mm objects) but offers no water protection. Useful for indoor equipment needing finer ingress protection against small debris and tools.
Detailed comparison
The stronger rating on each row is highlighted in emerald.
Solid protection (first digit)
IP21
2 — > 12.5 mm — Finger
IP40
4 — > 1 mm — Small Wires
Liquid protection (second digit)
IP21
1 — Vertically Dripping Water
IP40
0 — No Protection
Dust-tight
IP21
No
IP40
No
Water-jet resistant
IP21
No
IP40
No
Submersible
IP21
No
IP40
No
Outdoor suitable
IP21
No
IP40
No
The exact difference (IP21 vs IP40)
Solid protection
IP21
Level 2 — > 12.5 mm — Finger
IP40
Level 4 — > 1 mm — Small Wires
IP21 provides "> 12.5 mm — Finger" (level 2), while IP40 provides "> 1 mm — Small Wires" (level 4). IP40 is 2 levels higher.
Liquid protection
IP21
Level 1 — Vertically Dripping Water
IP40
Level 0 — No Protection
IP21 provides "Vertically Dripping Water" (level 1), while IP40 provides "No Protection" (level 0). IP21 is 1 level higher.
NEMA equivalents
No direct NEMA equivalent.
Recommendation
IP40 offers higher overall protection than IP21. Choose IP40 for harsher environments; IP21 may suffice for milder conditions and can be more cost-effective.