Highways Visibility and Sight Lines Calculator

Calculate required visibility splays and assess compliance with MfS and DMRB standards.

Road and Access Characteristics

Road Speed (mph)

Road Type

Access Type

X-Distance (setback from carriageway, metres)

Road Gradient (%)

Road Curvature

Pedestrian visibility required (2m × 2m minimum splay)

Cyclist considerations

Stopping Sight Distance (SSD) Required

Required Y-Distance (metres)

Adjusted for gradient; represents forward visibility requirement

Required Visibility Splay (Triangle)

X × Y dimensions for visibility triangle

Pedestrian Visibility Splay

Curve Visibility Adjustment

Compliance Assessment

Planning Condition Template

Suggested condition for decision notice

Standards Reference

Manual for Streets (MfS), Manual for Streets 2 (MfS2), Design Manual for Roads and Bridges (DMRB)