Traffic Signal Timing Calculator (Webster's Method)

Compute traffic signal cycle length and splits using Webster’s method.

Traffic Signal Timing Calculator

This calculator is designed for civil engineering professionals to determine optimal traffic signal timings using Webster's Method, enhancing traffic flow and reducing congestion.

Results

Optimal Green Time: --

Data Source and Methodology

All calculations are based on the formulae and data provided by the Webster's Method. All calculations rely strictly on the formulas and data provided by this source.

The Formula Explained

The formula to calculate optimal cycle time and green time is:

Cycle Time: \( C = \frac{1.5L + 5}{1 - \frac{\sum Y}{S}} \)

Green Time: \( G = C \times \frac{Y}{\sum Y} \)

Glossary of Variables

  • Cycle Length (C): Total cycle time in seconds.
  • Saturation Flow (S): Maximum flow rate of vehicles through the intersection.
  • Traffic Flow (Y): Actual flow rate of vehicles.
  • Green Time (G): Allocated green time for a phase.

How It Works: A Step-by-Step Example

For a cycle length of 90 seconds, with a saturation flow of 1800 vehicles/hour and a traffic flow of 900 vehicles/hour, the optimal green time is calculated using the formula:

G = 90 × (900 / 1800) = 45 seconds

Frequently Asked Questions (FAQ)

What is Webster's Method?

Webster's Method is a technique used to calculate optimal traffic signal timings to minimize delay and improve traffic flow efficiency.

Why is signal timing important?

Proper signal timing can reduce congestion, improve safety, and enhance the overall efficiency of a traffic system.

How do I use this calculator?

Enter the cycle length, saturation flow, and traffic flow to calculate the optimal green time using the provided formula.

Can this calculator be used for all intersections?

While it is based on standard calculations, specific intersection characteristics may require tailored adjustments.

Audit: Complete
Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.
Formula (extracted LaTeX)
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Formula (extracted text)
The formula to calculate optimal cycle time and green time is: Cycle Time: \( C = \frac{1.5L + 5}{1 - \frac{\sum Y}{S}} \) Green Time: \( G = C \times \frac{Y}{\sum Y} \)
Variables and units
  • T = property tax (annual or monthly depending on input) (currency)
Sources (authoritative):
Changelog
Version: 0.1.0-draft
Last code update: 2026-01-19
0.1.0-draft · 2026-01-19
  • Initial audit spec draft generated from HTML extraction (review required).
  • Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
  • Confirm sources are authoritative and relevant to the calculator methodology.
Verified by Ugo Candido on 2026-01-19
Profile · LinkedIn
, ', svg: { fontCache: 'global' } };

Traffic Signal Timing Calculator (Webster's Method)

Compute traffic signal cycle length and splits using Webster’s method.

Traffic Signal Timing Calculator

This calculator is designed for civil engineering professionals to determine optimal traffic signal timings using Webster's Method, enhancing traffic flow and reducing congestion.

Results

Optimal Green Time: --

Data Source and Methodology

All calculations are based on the formulae and data provided by the Webster's Method. All calculations rely strictly on the formulas and data provided by this source.

The Formula Explained

The formula to calculate optimal cycle time and green time is:

Cycle Time: \( C = \frac{1.5L + 5}{1 - \frac{\sum Y}{S}} \)

Green Time: \( G = C \times \frac{Y}{\sum Y} \)

Glossary of Variables

  • Cycle Length (C): Total cycle time in seconds.
  • Saturation Flow (S): Maximum flow rate of vehicles through the intersection.
  • Traffic Flow (Y): Actual flow rate of vehicles.
  • Green Time (G): Allocated green time for a phase.

How It Works: A Step-by-Step Example

For a cycle length of 90 seconds, with a saturation flow of 1800 vehicles/hour and a traffic flow of 900 vehicles/hour, the optimal green time is calculated using the formula:

G = 90 × (900 / 1800) = 45 seconds

Frequently Asked Questions (FAQ)

What is Webster's Method?

Webster's Method is a technique used to calculate optimal traffic signal timings to minimize delay and improve traffic flow efficiency.

Why is signal timing important?

Proper signal timing can reduce congestion, improve safety, and enhance the overall efficiency of a traffic system.

How do I use this calculator?

Enter the cycle length, saturation flow, and traffic flow to calculate the optimal green time using the provided formula.

Can this calculator be used for all intersections?

While it is based on standard calculations, specific intersection characteristics may require tailored adjustments.

Audit: Complete
Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.
Formula (extracted LaTeX)
\[','\]
','
Formula (extracted text)
The formula to calculate optimal cycle time and green time is: Cycle Time: \( C = \frac{1.5L + 5}{1 - \frac{\sum Y}{S}} \) Green Time: \( G = C \times \frac{Y}{\sum Y} \)
Variables and units
  • T = property tax (annual or monthly depending on input) (currency)
Sources (authoritative):
Changelog
Version: 0.1.0-draft
Last code update: 2026-01-19
0.1.0-draft · 2026-01-19
  • Initial audit spec draft generated from HTML extraction (review required).
  • Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
  • Confirm sources are authoritative and relevant to the calculator methodology.
Verified by Ugo Candido on 2026-01-19
Profile · LinkedIn
]], displayMath: [['\\[','\\]']] }, svg: { fontCache: 'global' } };, svg: { fontCache: 'global' } };

Traffic Signal Timing Calculator (Webster's Method)

Compute traffic signal cycle length and splits using Webster’s method.

Traffic Signal Timing Calculator

This calculator is designed for civil engineering professionals to determine optimal traffic signal timings using Webster's Method, enhancing traffic flow and reducing congestion.

Results

Optimal Green Time: --

Data Source and Methodology

All calculations are based on the formulae and data provided by the Webster's Method. All calculations rely strictly on the formulas and data provided by this source.

The Formula Explained

The formula to calculate optimal cycle time and green time is:

Cycle Time: \( C = \frac{1.5L + 5}{1 - \frac{\sum Y}{S}} \)

Green Time: \( G = C \times \frac{Y}{\sum Y} \)

Glossary of Variables

  • Cycle Length (C): Total cycle time in seconds.
  • Saturation Flow (S): Maximum flow rate of vehicles through the intersection.
  • Traffic Flow (Y): Actual flow rate of vehicles.
  • Green Time (G): Allocated green time for a phase.

How It Works: A Step-by-Step Example

For a cycle length of 90 seconds, with a saturation flow of 1800 vehicles/hour and a traffic flow of 900 vehicles/hour, the optimal green time is calculated using the formula:

G = 90 × (900 / 1800) = 45 seconds

Frequently Asked Questions (FAQ)

What is Webster's Method?

Webster's Method is a technique used to calculate optimal traffic signal timings to minimize delay and improve traffic flow efficiency.

Why is signal timing important?

Proper signal timing can reduce congestion, improve safety, and enhance the overall efficiency of a traffic system.

How do I use this calculator?

Enter the cycle length, saturation flow, and traffic flow to calculate the optimal green time using the provided formula.

Can this calculator be used for all intersections?

While it is based on standard calculations, specific intersection characteristics may require tailored adjustments.

Audit: Complete
Formula (LaTeX) + variables + units
This section shows the formulas used by the calculator engine, plus variable definitions and units.
Formula (extracted LaTeX)
\[','\]
','
Formula (extracted text)
The formula to calculate optimal cycle time and green time is: Cycle Time: \( C = \frac{1.5L + 5}{1 - \frac{\sum Y}{S}} \) Green Time: \( G = C \times \frac{Y}{\sum Y} \)
Variables and units
  • T = property tax (annual or monthly depending on input) (currency)
Sources (authoritative):
Changelog
Version: 0.1.0-draft
Last code update: 2026-01-19
0.1.0-draft · 2026-01-19
  • Initial audit spec draft generated from HTML extraction (review required).
  • Verify formulas match the calculator engine and convert any text-only formulas to LaTeX.
  • Confirm sources are authoritative and relevant to the calculator methodology.
Verified by Ugo Candido on 2026-01-19
Profile · LinkedIn