IP66 vs IP68
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP66 and IP68 are both IEC 60529 ingress protection codes, but they differ in liquid protection (level 6 vs 8). IP66 is rated for dust-tight and powerful water jets (12.5 mm nozzle), while IP68 provides dust-tight and continuous immersion (manufacturer-specified).
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).
IP68 is dust-tight and protects against continuous immersion in water under conditions specified by the manufacturer (typically deeper than 1 meter for prolonged periods). The standard for submersible and marine equipment.
Detailed comparison
The stronger rating on each row is highlighted in emerald.
Solid protection (first digit)
IP66
6 — Dust-Tight
IP68
6 — Dust-Tight
Liquid protection (second digit)
IP66
6 — Powerful Water Jets (12.5 mm nozzle)
IP68
8 — Continuous Immersion (manufacturer-specified)
Dust-tight
IP66
Yes
IP68
Yes
Water-jet resistant
IP66
Yes
IP68
Yes
Submersible
IP66
No
IP68
Yes
Outdoor suitable
IP66
Yes
IP68
Yes
The exact difference (IP66 vs IP68)
Solid protection
IP66
Level 6 — Dust-Tight
IP68
Level 6 — Dust-Tight
Both IP66 and IP68 share the same solid protection: Dust-Tight.
Liquid protection
IP66
Level 6 — Powerful Water Jets (12.5 mm nozzle)
IP68
Level 8 — Continuous Immersion (manufacturer-specified)
IP66 handles 100 kPa (Powerful Water Jets (12.5 mm nozzle)), while IP68 handles Specified by manufacturer (Continuous Immersion (manufacturer-specified)). IP68 provides 2 levels more liquid protection.
NEMA equivalents
Recommendation
IP68 offers higher overall protection than IP66. Choose IP68 for harsher environments; IP66 may suffice for milder conditions and can be more cost-effective.