• One finger to drag the map.
• A two finger pinch to zoom in and out.
• One tap to select a map.
• Double tap to zoom to that map.

• Accurately sized vessel.
• Vessel, which if drawn to scale would be too small to see.
• Vessel or navaid with unknown direction.

The choice of colours is entirely arbitrary, but I thought that they helped distinguish the vessel types.

• Cargo
• Tanker
• Passenger
• Hi Speed Craft
• Unspecified/Other
• Tug

The colours are derived from the AIS type information which only vaguely defines categories, so a RO-RO ferry might appear as a cargo carrying passenger vessel or a passenger carrying cargo vessel.

Automatic Identification System is a collision avoidance system for ships. As part of the global maritime safety system, ships over 300 gt are now required to broadcast their positions, speed and direction to other vessels in the area. The AIS data is collected by enthusiasts using a special VHF receiver and uploaded to ShipAIS.

Many existing maps only cover the land and not the sea, so I've had to generate my own with the following considerations:

• The map is not to be used for navigation. I've tried to make the maps acurtate, but I can't keep them up to date and I may have missed somethings.
• You want to see the boats and not the map so I've made the map pale.
• Since collecting data and generating maps is difficult and expensive, marine charts are often copyright. I have only used freely available data to generate the charts. See Acknowledgements for the list of sources used.

Using ShipPlotter

If you would like to contribute AIS data from ShipPlotter, click on Options->Sharing->Server and set:

• Server: www.aisliverpool.org.uk
• Port: 80
• Script: shipinfo.php

The 'forward data from server 1 to server 2' box should not be ticked if you are sharing with the COAA server. Please only upload your own AIS data to AISLiverpool.

AISLiverpool is an "upload only" server so the "upload only" and "Trust static info" options have no effect.

Alternatively, you can directly upload to ShipAIS.uk:

• Server: www.aisliverpool.org.uk
• Port: 80
• Script: shipinfo.php

Uploading to either AISLiverpool or ShipAIS should be equivalent. ShipAIS tends to have a quicker response, but I have better loging facilities at AISLiverpool in case there is a problem.

Raw AIS NMEA or AIVDM data

If you are not using ShipPlotter, you can also upload unprocessed AIS data to

• www.aisliverpool.org.uk (51.148.147.243)
• Port: 4000
• UDP data

Yes, only the "frontend" has changed. All the AIS data, AIS contributors, photos and forum are still the same.

I wrote the original site back in 2005 and maintaining it has gradually got more and more complicated. Much of the technology has changed since then and trying to get the code to run on a new server would be a lot of work and a lot more expense. Instead, I have spent my time working on a new look website that works on both desktop and mobiles and should be easier to maintain.

As you may have guessed, I'm not a graphics designer so the layout may be too small on some devices or too big on others. If you have suggestions for better layout, colours, text, etc or find things that don't work then either contact me or post them on the forum. I'm also happy to have ideas of things you would like to see on the website or ways to help people find their way around.

Unfortunately the upgrade was forced on me by my (ex)hosting company. They refused to support the aging hardware the website was running on and shut it down several times citing "security" issues, but refused to give me any details or evidence.

Ideally I would have moved the website to a new hosting company, but much has changed since I wrote it in 2005 (before mobiles!) and signifcant parts of the code no longer work (mainly database queries). Also, in order to get ShipAIS to run on modest hardware, there are serveral difference caching mechanisms to reduce the load on the server.

So I was looking at a significant rewrite of old code and re-implementing the caching servers, or starting afresh using modern frameworks. I used the Covid19 lockdown of 2020 to write a new website.

For those who have problems with the new website, I apologise. The website is written as a hobby by a single person so I could only do limited testing before launching the site, but I am trying to improve it.