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Traffic Signal Design Software


LinSig is our flagship product and is a comprehensive design and modelling package for traffic signal junctions either individually or in a network of several junctions. LinSig has been used throughout the UK since the mid 1980s and has consistently been the most widely used signal design software in the UK for over 20 years. Over this period LinSig has been extensively developed to stay at the forefront of traffic signal modelling.

The current version of LinSig is Version 3.2.

quickGreen 2

quickGreen 2 is the latest version of our graphical tool for measuring and calculating traffic signal phase intergreens.


TranEd is our graphical editor for TRANSYT V11/12. It provides an enhanced user interface for TRANSYT and includes a wide range of additional and improved facilities over TRANSYT V11/12 alone. TranEd has been available since 1998 and is now used by a wide range of TRANSYT users across the UK and overseas.

We also produce a viewer/reader for TranEd files. The reader is available free of charge to anyone and can be freely distributed.


FlowRound provides a graphical design tool for building Lane-Flow Diagrams for both un-signalled and traffic signalled roundabouts. These lane flow diagrams aid the design and development of lane structures for the roundabout and provide a robust starting point for more detailed analysis with tools such as TRANSYT or LinSig.

JCT TrafficTools Available Free of Charge

JCT TrafficTools is an Android phone/tablet app that can be used to assist in on-site data collection. It includes measurement of Saturation Flows, Degree of Saturation, and Underutilised Green Time, and this beta version is now available free of charge from the Google Play Store.

LINSAT Available Free of Charge

LINSAT is an analysis package for estimating saturation flow for complex flared approaches to traffic signals. It uses a simulation based technique to adjust saturation flows to take account of features such as lane under-utilisation and blocking. This is now available free of charge from our download page.


Upcoming courses

21 Oct 2024: Introduction to Traffic Signals ...more

23 Oct 2024: LinSig3 : Junction Modelling Computer Workshop ...more

14 Nov 2024: Online Advanced Traffic Signal Design ...more

21 Jan 2025: Online Introduction To Traffic Signals ...more

04 Feb 2025: LinSig3 : Online Junction Modelling Computer Workshop ...more

...view full schedule

...view course descriptions


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