IP25 vs IP66
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP25 and IP66 are both IEC 60529 ingress protection codes, but they differ in solid-object protection (level 2 vs 6) and liquid protection (level 5 vs 6). IP25 is rated for > 12.5 mm — finger and water jets (6.3 mm nozzle), while IP66 provides dust-tight and powerful water jets (12.5 mm nozzle).
IP25 is an ingress protection code that ensures protection against solid objects larger than 12.5 mm and protection against water jets. Water projected by a 6.3 mm nozzle against the enclosure from any direction shall have no harmful effects.. It is an IEC 60529 ingress protection code combining first-digit (solid) level 2 with second-digit (liquid) level 5.
IP66 is dust-tight and resists powerful water jets (12.5 mm nozzle, 100 kPa). A robust outdoor rating for equipment exposed to heavy rain, storms, or directed high-pressure hosing (but not high-pressure washdown).
Detailed comparison
The stronger rating on each row is highlighted in emerald.
Solid protection (first digit)
IP25
2 — > 12.5 mm — Finger
IP66
6 — Dust-Tight
Liquid protection (second digit)
IP25
5 — Water Jets (6.3 mm nozzle)
IP66
6 — Powerful Water Jets (12.5 mm nozzle)
Dust-tight
IP25
No
IP66
Yes
Water-jet resistant
IP25
Yes
IP66
Yes
Submersible
IP25
No
IP66
No
Outdoor suitable
IP25
Yes
IP66
Yes
The exact difference (IP25 vs IP66)
Solid protection
IP25
Level 2 — > 12.5 mm — Finger
IP66
Level 6 — Dust-Tight
IP25 provides "> 12.5 mm — Finger" (level 2), while IP66 provides "Dust-Tight" (level 6). IP66 is 4 levels higher.
Liquid protection
IP25
Level 5 — Water Jets (6.3 mm nozzle)
IP66
Level 6 — Powerful Water Jets (12.5 mm nozzle)
IP25 handles 30 kPa (Water Jets (6.3 mm nozzle)), while IP66 handles 100 kPa (Powerful Water Jets (12.5 mm nozzle)). IP66 provides 1 level more liquid protection.
NEMA equivalents
No direct NEMA equivalent.
Recommendation
IP66 offers higher overall protection than IP25. Choose IP66 for harsher environments; IP25 may suffice for milder conditions and can be more cost-effective.