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BLOS/BCI Calculator Form

To calculate Bicycle Level of Service (BLOS) and Bicycle Compatibility Index (BCI) of a particular roadway section, fill out the following for the typical cross-section. Results will pop up in a new window. Default values will be used for any fields left empty.

Some details on the BLOS input fields and their ranges are here. Further information and references on these measures are here.

Through lanes per direction: (Default = 1)
Width of outside lane, to outside stripe, in ft: (Default = 12)
Paved shoulder, bike lane, OR marked parking area - outside lane stripe to pavement edge, in ft: (Def=0)
Bi-directional Traffic Volume in ADT: (Default = 4000)
Posted speed limit in mph: (Default = 30)
Percentage of heavy vehicles: (Default = 2)
FHWA's pavement condition rating: (5 = Best, 1 = Worst; Default = 4)
Percentage of road segment with occupied on-street parking: (Default = 0)
On-street parking time limit, in minutes: (Default = 120)
Goes through residential area?: (Default = No)


BLOS Data Input Fields

The following provides further information on the BLOS data inputs. See the references for more, including BCI details.

Roadway parameters will often change, and averaging could be done depending on the situation. In general, try to select a typical cross-section.


Through lanes per direction:Do not include medians, turn lanes, or continuous-left-turn lanes.
Width of outside travel lane, to outside stripe (in feet):Width of right-most travel lane, excluding striped paved shoulders, bike lanes, and marked parking stalls.
Paved shoulder, bike lane, OR marked parking area, outside lane stripe to pavement edge (in feet): Besides a paved shoulder or a bike lane, this width may also be marked (striped or hashed) parking stalls. For diagonal parking, use the perpendicular distance from the end of the parking stripes to the pavement edge. This calculator does not work when there are BOTH bike lanes and parking stalls - please see the reference for this case.
Bi-directional Traffic Volume (in ADT):Daily average. Assumed Directional factor (0.565) and Peak Hour Factor (0.091) values are used in a conversion to peak 15-minute volume.
Percentage of heavy vehicles:As defined in the Highway Capacity Manual.
Percentage of road segment with occupied on-street parking:Exclude driveways. Either one side or an average of both sides may be considered at a time.

Model parameter ranges

The BLOS model was developed using roads with the following parameter ranges:

  • Through lanes per direction - 1 to 3 (2 to 6 lane roads)
  • Width of outside travel lane, to outside stripe - 10 to 16 feet
  • Paved shoulder or bike lane, outside lane stripe to pavement edge - 0 to 6 feet (no rumble strips)
  • Bi-directional traffic volume - 550 to 36,000 ADT (Average Daily Traffic)
  • Posted speed limit - 25 to 50 mph
  • Percentage of heavy vehicles - 0 to 2%
  • FHWA's pavement condition rating - 5 (very good) to 2 (poor)
  • A wide range of development types and parking conditions

(Be aware of model use outside these ranges, particularly for paved shoulders much over 6 feet and more than a few percent heavy vehicles.)

BLOS/BCI Page


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Formula correction and further details added 2006-09-12
Cosmetic revisions 2004-05-03
Created 2003-10-28
Lee Pirtle,