Level of Service (LOS) Helper
Enter average control delay (seconds/vehicle) to instantly get the HCM Level of Service grade (A–F) for a signalized intersection.
Signalized Intersection LOS
Enter the average control delay from your traffic study or simulation output.
A
Level of Service
LOS A
Enter a delay value and click Get LOS
Thresholds per HCM 7th Edition, Table 19-3 — Signalized Intersections only.
HCM LOS Reference Table
Signalized intersection LOS grades per HCM 7th Edition.
| LOS | Control Delay (s/veh) |
|---|
LOS F applies when demand exceeds capacity regardless of delay value.
Summary
Enter average control delay (seconds/vehicle) to instantly get the HCM Level of Service grade (A–F) for a signalized intersection.
How it works
- Enter the average control delay per vehicle in seconds (from a traffic study or simulation output).
- The tool compares your delay value against HCM 7th edition LOS threshold table.
- The LOS grade (A through F) is displayed immediately with a color-coded badge.
- A reference table shows all six LOS grades and their delay ranges for context.
- Use the result to evaluate intersection performance or support a transportation study.
Use cases
- Quickly classify intersection performance from a traffic count or simulation.
- Verify LOS grades during transportation impact study preparation.
- Teach students the HCM LOS concept with an interactive reference.
- Cross-check outputs from traffic software such as Synchro or VISSIM.
- Screen multiple intersections by pasting delay values one at a time.
- Document LOS results in traffic engineering reports.
Frequently Asked Questions
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Last updated: 2026-05-23 ·
Reviewed by Nham Vu