How often should site links be checked

I normally try to check external links on the site every 3 months or so. I'd like to check more often but I just see it as a severe hit to my server, because the link checker program has to read every page. At the same time it's a lot of work to use this program because at any given time there are always a few dozen websites off-line for what ever reason, so I have to recheck those. Of course how many companies could go out of business or change hands in a three month time period.

Any way this time around there were about 20 bad links including 3 from me, pointing to a misspelled address on my own site. I still have a few more links in my to-do box, waiting a few days to see if they come back on-line. The attached graphic shows the data produced by the link checker program. Over 99.5% of the links were good, but I didn't track all the link conditions. The report indicates I have 7,815 external links and 1,917 internal [page-to-page] links; because there are 1,917 pages that make up the web site.

So if you have external links it's always a good idea to keep them up to date. You never know who buys up the link once its gone bad. Search engines don't like broken links and of course visitors never like bad links, they just make the site seem abandoned. Oh I should also say I tried using the program over the last few week but just kept getting to many broken internal links in the report making the report impossible to use ~ the program was over-loading my server. The program and server worked ok today....

At the same time I fixed those bad links I also made what ever updates were required on the 20 pages that were 'fixed', making the process take twice as long as it needed.

Click to enlarge the graphic.