IP21 vs IP33
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP21 and IP33 are both IEC 60529 ingress protection codes, but they differ in solid-object protection (level 2 vs 3) and liquid protection (level 1 vs 3). IP21 is rated for > 12.5 mm — finger and vertically dripping water, while IP33 provides > 2.5 mm — tool / wire and spraying water (up to 60°).
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.
IP33 protects against tools and 2.5 mm objects plus spraying water up to 60° from vertical. A practical rating for indoor equipment subject to light spray or for sheltered outdoor fixtures.
Detailed comparison
The stronger rating on each row is highlighted in emerald.
Solid protection (first digit)
IP21
2 — > 12.5 mm — Finger
IP33
3 — > 2.5 mm — Tool / Wire
Liquid protection (second digit)
IP21
1 — Vertically Dripping Water
IP33
3 — Spraying Water (up to 60°)
Dust-tight
IP21
No
IP33
No
Water-jet resistant
IP21
No
IP33
No
Submersible
IP21
No
IP33
No
Outdoor suitable
IP21
No
IP33
No
The exact difference (IP21 vs IP33)
Solid protection
IP21
Level 2 — > 12.5 mm — Finger
IP33
Level 3 — > 2.5 mm — Tool / Wire
IP21 provides "> 12.5 mm — Finger" (level 2), while IP33 provides "> 2.5 mm — Tool / Wire" (level 3). IP33 is 1 level higher.
Liquid protection
IP21
Level 1 — Vertically Dripping Water
IP33
Level 3 — Spraying Water (up to 60°)
IP21 handles 0.1 mm/min drip rate (Vertically Dripping Water), while IP33 handles 80 kPa (tube) / 50 kPa (nozzle) (Spraying Water (up to 60°)). IP33 provides 2 levels more liquid protection.
NEMA equivalents
No direct NEMA equivalent.
Recommendation
IP33 offers higher overall protection than IP21. Choose IP33 for harsher environments; IP21 may suffice for milder conditions and can be more cost-effective.