How To Make a Tag Cloud
By Pete Freitag


Jeffery Zeldman proclaims that tag clouds are the new mullets. However, as I'm sure you're aware some people just can't resist the mullet.
I actually find my tag cloud quite handy because it lists all my tags on one page, and I can see what topics I post about most frequently quite easily. I also use it as a way to see which tags I have already used, so I can be consistent when tagging posts.
Anyways a lot of folks would like to know just how you can get one of these mullets, er tag clouds. I have shown how I do it below using CFML. If you don't use ColdFusion you should still be able to follow along.
At this point you may be wondering what's a tag cloud? If so consult the picture below:
Ok, now let the mullets reign...
Step 1 - Get a list tags, and their frequency
<cfquery datasource="#dsn#" name="tags"> SELECT COUNT(tag) AS tagCount, tag FROM tblblogtags GROUP BY tag </cfquery>
In my tag cloud I list all my tags, but if you have a lot of tags you may want to limit the min number of occurrences using a HAVING
statement. For example HAVING tagCount > 5
Step 2 - Find the Max and Min frequency
<cfset tagValueArray = ListToArray(ValueList(tags.tagCount))> <cfset max = ArrayMax(tagValueArray)> <cfset min = ArrayMin(tagValueArray)>
Step 3 - Find the difference between max and min, and the distribution
<cfset diff = max - min> <cfset distribution = diff / 3>
You can define the distribution to be more granular if you like by dividing by a larger number, and using more font sizes below. You will probably need to play with this to get your tag cloud to look good.
Step 4 - Loop over the tags, and output with size
<cfoutput query="tags"> <cfif tags.tagCount EQ min> <cfset class="smallestTag"> <cfelseif tags.tagCount EQ max> <cfset class="largestTag"> <cfelseif tags.tagCount GT (min + (distribution*2))> <cfset class="largeTag"> <cfelseif tags.tagCount GT (min + distribution)> <cfset class="mediumTag"> <cfelse> <cfset class="smallTag"> </cfif> <a href="/tag/#tags.tag#" class="#class#">#tags.tag#</a> </cfoutput>
Step 5 - add css classes to your stylesheet
.smallestTag { font-size: xx-small; } .smallTag { font-size: small; } .mediumTag { font-size: medium; } .largeTag { font-size: large; } .largestTag { font-size: xx-large; }
There are probably lots of different ways to build a tag cloud, but this is the first method that came to mind.
How To Make a Tag Cloud was first published on June 24, 2005.
If you like reading about tags, blog, tagging, folksonomy, tag cloud, cfml, or tips then you might also like:
- Make your blog better with tags
- Increase Productivity with Action Tagging
- Related Posts
- Visualization of my del.icio.us tags
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Comments
http://www.francisshanahan.com/taglines/default.aspx?cat=All
it's an auto-folksonomy tool built using the Term Extraction APIS.
It combines Ajax with Folksonomies and Yahoo Web Services to allow you
to search on RSS feeds, News, Movies, Images or just obtain the
original story, all without a page-refresh.
Would love to get some feedback on it or suggestions for improvement.
regards,
-fs
I need to implement this on my site www.similarthings.com :) Minus the mullet!
Did you sign up? You should check it out, I have added some nice Ajax and Effects to some of the admin.
I did the font sizing a bit differently, but it's the same basic premise.
The task I'm working on now, however is: How would one add the capability to display at least one tag for every letter of the alphabet?
Assume for a second that you have 5500 tags in your tag table. That's alot of tags to display - so what I would want to do is find enough tags to fill out a max of 100 tags, for instance, with at least one tag from each letter of the alphabet. (otherwise, you might have the first 100 tags be A-G, rather than A-Z...looks strange to users, and skips cool content in the H-Z range)
Anyway, tags are cool, and thanks for the ideas!!
I used your ideas here: http://www.rel8r.com/tags/
i loved the idea of having my own tag cloud. i tried eurekstr and zoomcloud but this seems like a better idea.
I tried cutting an pasting this in my template under the sidebar section and I get no results. I also tried adding <script> and </script> after now the #tag thingies disappear but there is no tag cloud.
I know that I doing something wrong. I hope it is simple and I hope you can help.
I was just talking with a friend about how to create a tag cloud for my blog but I wasn't sure how to go about it.
Although I don't use ColdFusion, your article was (as you said!) easy enough to follow. I'm going to get to work on creating my own tag cloud today! (I use WordPress as my blogging engine so I guess I'll be writing my code in PHP as a plugin.
Thanks for this helpful article!
http://en.dahnielson.com/2006/07/blog-overcast-tagclouds.html
I only started looking into tag clouds since yesterday and I have to say I am a bit confused.
I am an excellent user on html and DreamWeaver but I have never touched Coldfusion.
Does anyone now any other articles or tutorials that would help me understand more about tag clouds, where they are used and how!
Some of my questions:
Are they only or mainly used for blogs?
What kind of tags do I use to link the key words with the tag link generator (tag cloud links I supose).
Does the above script goes in the head or the body of the page.
As you can understand I am completely lost.
Thank you all in advance
http://www.taskfly.com/blog/?p=6
http://www.featurepics.com/editorial/tag-cloud.aspx
We have added a little bit "colors" to the final styling (selected a main color and blended it).
http://www.gencler.info
It's very cool.
It's very cool.
One question though, how do you recommend dealing with multiple tags for an entry? I initially set up a test DB Table that had a "tag" field with multiple tags separated by a comma, obviously this code wasn't able to break up the list into various keywords, and simply grouped them all into one big tag. Looking through it I don't really see how it could be modified to deal with a list.
Is having a separate tags table that is then linked back to the master record the answer? That seems like the only plausible way, as having only one tag per record seems very limiting.
http://pastebin.com/f1d04c178
And, for those asking about the db table, it should look something like..
(Here's to hoping it lines up..)
+---------+-------------+
| Field | Type |
+---------+-------------+
| id | numeric |
| tag | varchar |
+---------+-------------+
The today blog structure have more than one tag.
So your new blog table might look like this.
"BlogId", "Title", "Description", "Content", "Date", "AuthorId" and "Tag"
You can try cold like
1. Pull all the Tags from the table,
2. Create a new query with "Tag" and "TagCount" and populate it with step 1.
3. You can know continue from step 1 of the this original post.
Looks like a loot of code, you might catch your result for better performance.
http://www.irtouring.com/default.aspx?id=28#tagcloud
I want to add a tag cloud to my website but i don't know if it can be added to a simple HTML website..? Also, i am not a technical person... could just do very small things in HTML. so would this code work for me as well or is there a better option for me.
Many thanks in advance for your response.
Awesome post, just want to say thanks for the share
thanks alot for posting this, along with some code... much appreciated ;)
/foO