Frequently Asked Questions

The KnightVision PGN Viewer is a tool to publish chess games using PGN files in websites or blogs so others can play over them. It was created in 2008 and serves up millions of chess games every year.

KnightVision PGN Viewer: Introduction

What about the KnightVision PGN Viewer on an iPad or Android tablet?

When Flash is not supported the viewer will display the non-flash version. It currently shows the text of the moves. The text of the moves are followed by a link for the KnightVision mobile chess app. For an example, see this blog post (always non-Flash) or this post (Flash if it is supported or non-Flash otherwise) from an iPad or Android tablet.

What is PGN?

PGN stands for Portable Game Notation and is a standard way to record and store a chess game. Online chess servers (like ICC and FICS) can send you your games in pgn format and chess database software can read and export to PGN files.

What is the purpose of the KnightVision website and KnightVision PGN Viewer?

Our mission is to have fun and allow you to publish chess games including commentary, analysis and variations to your web site or blog to share and educate others.

How do I use the KnightVision PGN Viewer to view a game?

Use the VCR-like (forward, back, etc) controls on the bottom of the board to move through the game. There is also a flip button to reverse the orientation of the board. The white or black square at the bottom right of the board inidcates which side is on move. To access the PGN data of the game, click the copyright message above the moves and you will be taken to the KnightVision PGN publish tool with that data in the PGN text box.

How much does it cost?

It is free.

What uptime or quality or service level do you guarantee?

None. Use the PGN Viewer and KnightVision web site at your own risk.

Where can I publish to using the KnightVision PGN Viewer?

You can publish your games to any web site that allows you to use full html including the embed and object tags with javascript and flash. Blogger is our target.

WordPress hosted blogs do not currently work with the KnightVision PGN Viewer, but, if you have your own WordPress site you can use KnightVision with the plugin written by Pepijn van Erp. See and

Can I see examples web sites using KnightVision?

Sure, here are a few.

GM Michael Adams

Chicago Chess Blog

Bennett and King On Chess

I Playoo Chess

Nau64 Chess Club

Old in Chess



Chess on the Borderline

Abruzzo Scacchi

Ajedrez en el Umbral


Mike Serovey on Chess

Glenn Wilson

How do I get started?

For a quick start watch the video above and then go to

How can I customize KnightVision PGN Viewer to match my blog or website colors better?

You don't need to do anything but if you want to customize or improve how KnightVision blends in with the rest of your site you can customize the colors used.

The most important options for matching your colors when you publish are the Color Theme and the Background Color Override:

KnightVision Pub Options

First, the Background Color Override. If your background is white you don't need to do anything with the Background Color Override. That is the default background color. If your background color is black, you can enter "0" (without the quotes). For other colors, enter the 6 character hex color into the Background Color Override field. In the picture above I have entered "f6f6f6". If you don't know your background color value you can look at your blogger termplate or css files or do a little experimentation. A useful technique is: How to grab the hex code for any color on your screen. Also see this or this for help finding or selecting colors. If your background is an image, try selecting a color from the image or surrounding elements in your web page or blog.

You can then pick one of the pre-defined color themes that best match your blog or website. To see what each looks like, select it and then preview it in the KnightVision PGN Quick publisher.

For more custom effect, you can also pick a dark color override. This is the hex color value that will be used for the dark squares of the chess board and a few other areas.

How can I download the PGN as a file or copy it to the clipboard when viewing a chess game in the viewer?

If the person that published the game chose to show the moves (did not select "Board Only") when they published it then the PGN is available. You can click on the area just above the moves text where is says "Click here to view pgn". That will open the publishing page on the KnightVision web site with the text of the PGN data in the PGN text box. You can copy and paste it from there. There is a length limitation for the PGN data accessed in this manner and longer PGN data may be truncated.

What if KnightVision is having problems understanding my PGN file?

KnightVision understands valid PGN and if you are using PGN generated by a tool there should be no problems. But some common problems from manual editing or copy-n-paste errors do happen.

If you enter bd2 for Bd2 when you enter the game you will see "**Impossible or ambiguous move:(bd2 ) **". First, what is wrong with bd2? The issue is that the pieces must be specified with an upper case letter. So, "Bd2" would be fine. Also, "Bc1-d2" would work. The PGN specification requires pieces in moves to be represented as upper case characters. Also, note that Nd2 would not be recognized as a valid move if there were two knights that could move to d2. It needs to be clear which one is intended. To do that you could use "Nbd2". KnightVision will also recognize "Nb1-d2" or "N1d2".

Another issue to keep in mind is that the destination square must be fully specified in the move. This is mostly an issue with pawn captures. Use "exd6" or "ed6" but not just "ed".

Also, after a problem, we may seem to have a problem in each of the variations later. Those all may be an artifact of the first error. Since KnightVision is confused as to the position it thinks the subsequent variations are attempting illegal moves. If the subsequent moves look ok, it is best to just fix the first error and try again.

What if I want to host the KnightVision Viewer on my site or serve a game from a PGN file on my site?

You can do that. To host a PGN file from your site you will also need to host the viewer on your site. Here is an example of doing that where the viewer and the game displayed are not being served from this KnightVision web site. View this web page source and search for ".swf" to see how it is done. Contact me for additional help. To download the KnightVision PGN Viewer swf file, your may download and rename it to KnightVision.swf.

What if I want to make other changes to the KnightVision PGN Viewer?

You can do that, it is open source. The link to the source is near the bottom of the KnightVision PGN Viewer page. Contact me for additional help.

© 2008-2013 by Glenn Wilson. All rights reserved.