IP64 vs IP51
Head-to-head comparison of two IEC 60529 ingress protection ratings.
IP64 and IP51 are both IEC 60529 ingress protection codes, but they differ in solid-object protection (level 6 vs 5) and liquid protection (level 4 vs 1). IP64 is rated for dust-tight and splashing water (all directions), while IP51 provides dust-protected and vertically dripping water.
IP64 is dust-tight and resists splashing water from any direction. A solid outdoor-covered rating combining complete dust exclusion with splash tolerance, sitting between IP65 (jets) and IP54 (dust-protected).
With IP51, an enclosure receives dust-protected (limited ingress, no harmful deposit) and protection against vertically falling drops of water. Dripping water shall have no harmful effects.. It is an IEC 60529 ingress protection code combining first-digit (solid) level 5 with second-digit (liquid) level 1.
Detailed comparison
The stronger rating on each row is highlighted in emerald.
Solid protection (first digit)
IP64
6 — Dust-Tight
IP51
5 — Dust-Protected
Liquid protection (second digit)
IP64
4 — Splashing Water (all directions)
IP51
1 — Vertically Dripping Water
Dust-tight
IP64
Yes
IP51
Limited
Water-jet resistant
IP64
No
IP51
No
Submersible
IP64
No
IP51
No
Outdoor suitable
IP64
Yes
IP51
No
The exact difference (IP64 vs IP51)
Solid protection
IP64
Level 6 — Dust-Tight
IP51
Level 5 — Dust-Protected
IP64 provides "Dust-Tight" (level 6), while IP51 provides "Dust-Protected" (level 5). IP64 is 1 level higher.
Liquid protection
IP64
Level 4 — Splashing Water (all directions)
IP51
Level 1 — Vertically Dripping Water
IP64 handles 50–100 kPa (Splashing Water (all directions)), while IP51 handles 0.1 mm/min drip rate (Vertically Dripping Water). IP64 provides 3 levels more liquid protection.
NEMA equivalents
No direct NEMA equivalent.
No direct NEMA equivalent.
Recommendation
IP64 offers higher overall protection than IP51. Choose IP64 for harsher environments; IP51 may suffice for milder conditions and can be more cost-effective.