What happens when you take away the URL from a blog comment form?

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When we launched our marketing site redesign several weeks ago, I decided to do a little experiment with our blog. I removed the URL input field for blog comments, because I wanted to see how it would affect the quality and quantity of comments.

Why do people comment?

I predicted that removing the URL input field would result in:

  • Fewer comments
  • URLs inside of comments
  • URLs submitted by bots

All three predictions came true.

Fewer comments

Genuine comments usually appear when we announce an interesting new feature, or broach a controversial subject. Sometimes there’s just one comment, and sometimes there are 20.

Most of the time, we blog about small (but significant) changes to the system. Those entries are are meant to keep our customers informed about changes, and generally don’t evoke a response. Upon launching the new blog design without the URL input field, we saw saw comments dramatically drop on those types of entries.

Link Spam

While there has been a decrease in comments, we’ve seen an increase in URLs being left in the comments. The vast majority of those links have been unrelated to the blog entry, promotional in nature only.

This type of commenting behavior leads the moderator to believe that the commenter’s motives are disingenuous.

Bot spam

During the experiment, bots, or the software that’s used to comment on blogs, were easy to spot because they had URLs! Whenever I saw any comment that was submitted with a URL, I knew immediately who was spamming us.

Should the URL input field be used?

The short answer is yes. Whether or not comments are used for self-promotion, well moderated comments are beneficial to the blog and the readers. There are a few benefits to including the URL:

  • It provides a public reference point to who the commenter is.
  • It encourages more participation, which increases user generated content.
  • It keeps people with good ideas from junking up their comments with self-promotional links.

I’m adding the URL input field back for those reasons.

When it comes to blog comments, I think there are two good approaches. You either turn comments off completely, or allow commenters to leave all of the details they want, including the URL.

17 Responses to “What happens when you take away the URL from a blog comment form?”

  1. There you have it. Spammers will spam comments no matter what you do. I have tried a lot to stop it on my blog but 99.9% of comments that come in are still absolute rubbish. And, don’t get me started on contact forms!

    Keep your eyes out for the SEO Dojo Radio this week. Seems like comment linking has quickly popped up as a hot topic for the week.

    All the best!

  2. A post around some of my thinking over the last month or so. Our blog allows standard commenting through wordpress un-edited.

    When we complete a few tweaks over the next week or so, we will actually be going in the other direction by not only continuing to allow urls, but also make those urls do follow…

    We will have a set of guidelines, for instance only those comments that add value will be approved, sites will be checked for authenticity and lastly the ‘name’ must be their personal name or company name (no additional keywords).

    It will be interesting to see the results and what we notice over a period of 4 – 8 weeks. I plan to do a guest post somewhere to detail our results and findings.

  3. Tom Demers

    Yeah agreed – I actually really like the idea of allowing followed comment links and heavy moderation as in theory it incentivises more and better comments (like letting guest bloggers link out liberally), but in reality there probably aren’t a ton of businesses where the cost/benefit of having to invest tons more time in moderating due to the HUGE uptick in spammers/low value comments makes any sense.

    Anyway thanks for sharing!


  4. Sam Crocker

    Hey Jon,

    Very interesting test and I can’t say I’m shocked to see that any of the predictions you made came true. It seems like it’s well worth leaving the URLs in, so long as it means people are leaving thoughtful and meaningful responses. And aren’t trying to get too creative with anchor text links and the like.

    I imagine it was a bit entertaining to watch people include the URL in their comments (I always love to see the non-moderated spam attempts including the href= nonesense), but I think you’ve made some good points.

    Are you able to share anything more about the level of spam/bot activity as you removed the URL field? Was it a marked increase, or just a minor increase?

    Thanks for sharing the results and keep up the good work.

  5. Pretty interesting study. I was amazed at how big of an impact it had on the total number of comments. I really thought that if someone had an opinion on a post they would share it regardless of whether or not they got something from it. I guess the big question is, what was the impact on the quality of comments?

  6. Jason Jones

    Comment spam is a really tough one to crack… Even when I have implemented captchas and other forms of security I still find a pretty good share of comment spam making it through.

  7. Jon Henshaw

    Sam, it was entertaining, as spam usually is. The spam bot activity wasn’t that high. I think Akismet still caught most of it. But there were several comments left that didn’t get caught as spam that had URLs. It was quite amusing to see these sites so blatantly exposed.

    One other caveat is that those comments were actually well written. And by well written, I don’t mean they’re winning an award for prose, but they were on topic and referenced the blog entry. That tells me that there’s probably some custom software that aggregates feeds, and allows the user to read and comment without even visiting the blog. That’s actually not difficult to code at all, so I think that’s a very plausible assumption of how they were doing it.

  8. Jon Henshaw

    Charlie & Taylor, comment quality was slightly better, but I think there’s good user generated content to get from people who also want a link. Minus the blatant spammers, I think there’s an unwritten expectation that if you spend the time to provide a thoughtful comment, you want to be rewarded by a reference link, and I’m completely fine with that.

  9. Interesting. I always leave the URL field off of the custom blogs I develop. I know it will reduce the amount of comments I get, and I actually think that’s a good thing. The URL incentive just encourages spam, and it also encourages low quality comments where the commenter is just trying to come up with something relevant to say, but doesn’t actually have anything to contribute to the conversation. Leaving the URL field off means dealing with a LOT less spam and useless “great post!” comments. The only downside I really see is losing that public reference point to who the commenter is. Perhaps I’ll start adding a twitter handle instead, but I’m still not convinced that the URL field on blog comments provides enough benefit to make it worth including. Sure, I’ll get fewer comments, but that’s fine. I don’t want comments that were only added for the link.

  10. Justin Seibert

    Great experiment – always interesting to see if what you expect holds true when you actually apply changes. Thanks for sharing.

    I think there are a couple more reasons to use the url field as well, but the most significant one that you listed is providing the reference point to the commenter. I click on these often to provide more context to the conversation when I’m following a thread. That could be achieved as well by requiring the user to sign in with an existing social media profile, but I’ve always found those too restrictive and think they hurt comment volume as well.

  11. Charlie Southwell

    Very interesting experiment. I have taken to a moderating comments on my blogs before they go live now.

    I would ask the question that Taylor did – were the quality of comments you received better because of removing it? Or were they all (or mainly) the spam comments with urls in them?

  12. As a brand-new blogger, I would welcome people to leave comments on my blog, even if it’s only for self-promotion. I can easily imagine, however, that the larger the blog, the more headaches the moderation causes. I think, in the long run, that’s a good problem to have.

    Good job with the experiment.

  13. Or Weissler

    I agree along with your results. Enabling any commenter to
    be able to depart a web link is apparently appropriate netiquette. Even when
    you may not it truly is “nofollow. inches