The pictures you see on the left of some comments are Gravatars provided through gravatar.com.

Gravatar is a free, independent service that provides little avatars for registered users on Gravatar-enabled sites, like this one. Gravatar has FAQs and help documents on their site, but here's what you need to know.

The basics

  • Gravatar's basic service is free.

  • You sign up for their service by submitting your e-mail address and choosing a password.

  • They'll send you an e-mail to verify that you own that address.

  • You'll then need to upload an image to their website.

  • Your image will be given an MPAA-style rating by a Gravatar administrator.

  • After you've been rated your image will begin appearing on Gravatar-enabled sites.

  • Your Gravatar is displayed according to the e-mail address you enter in the comment box, so you must enter the e-mail address you registered with gravatar.com or your image will not display.

So! Pick your image, sign up, upload, and you're all set.

The no-so basics

  • Your Gravatar will be automatically resized to 80 pixels by 80 pixels, so perfectly square images give the best results.

  • The image rating process is not instantaneous. It may take anywhere from several minutes to several weeks for your Gravatar to be rated. (I waited about a day for my rating.) Because of this delay, you should choose your Gravatar wisely, as you will not be able to immediately select a replacement.

  • The most common Gravatar-enabled site is HaloScan. So in addition to your Gravatar appearing here, it will also appear in any HaloScan comments you leave, both on your own site and on other sites.

  • The owner of any Gravatar-enabled sites can set their own content level, so adult images may not appear on all sites. This blog is set to allow all content levels.

  • On this site, the e-mail address you provide will not be displayed. Other Gravatar-enabled sites may work differently.

  • Your Gravatar is completely independent of Blogger, Livejournal, MySpace and every other site that operates it's own avatar or profile photo system.

The really not-so basics

  • Information on Gravatar-enabling your own site can be found on the gravatar website.

  • I'm using the plugin for WordPress 1.2, which also seems to work just fine in WordPress 2.0.1.

    Update: I'm now using Skippy's much nicer Gravatars 2.6.

    Update: I'm now using Kip Bond's still nicer Gravatars2 2.6.0. It's based on Skippy's excellent plugin and includes excellent cache management with cron updating and local Gravatars for a configurable number of user levels.

  • The URL to retrieve a Gravatar is secure, and does not display a user's e-mail address in clear text. Instead it uses an MD5 hash for image retrieval, so there's no risk of a spambot crawling your site to harvest your user e-mail addresses.

Information specific to this site

  • As mentioned above, I am using Kip Bond's Gravatars2 plugin. The nicest part of Kip's implementation is the caching. Normally I'm not such a big fan of caching, especially for sites that don't have a very heavy load. The caching enabled with this plugin is one of the few exceptions.

    Gravatar.com's servers have been under a terrible strain lately. For the past several months, they've been very slow and very unreliable. Gravatars2 has options to completely neutralize that, but it does carry it's own cost.

    First, I've got the caching turned on. The Gravatars you see on this site are not loaded directly from gravatar.com. They are instead stored on my own domain. When you view a page, the images are loaded as fast as the rest of the page.

    Second, I've got the plugin set to never manually fetch a new Gravatar. The user interface, the front end, the pages you actually see, never downloads Gravatars. This keeps my page loads crisp.

    Third, I've set a cron job to automatically refresh the cache every few hours. If a certain Gravatar is new and has never been retrieved before, it will always be fetched on the next refresh. The same is true for errors, when gravatar.com did not respond properly and quickly to an image request. Gravatar2 includes full cron support and also includes a module to leverage WP-Cron if you require it.

  • Unfortunately, there's nothing that can completely insulate me from gravatar.com's performance issues. Every Gravatar must be retrieved at least once and any cache must include an expiry for it's contents. There will be a gap in Gravatar availability anytime the first comment is placed with a particular e-mail address or a cached image expires and gravatar.com doesn't supply a new one. This can lead to more than a few "Hey, where's my grav?" questions.

  • There is a solution to that as well, though not necessarily a perfect one. Gravatars2 allows "local Gravatars," which I suppose just makes them "avatars." The plugin allows registered users (of a user level chosen by the blog administrator) to specify an image to be used in place of a Gravatar. This feature supports JPG, GIF and PNG. Animation and transparency are also supported. However, it does not support file uploads. Each user must provide a url to the image they'd like to use. This image is then copied to the cache, from which it is read on each page load. If you decide to make use of this feature here, please make your images 50 pixels square.

  • Update: I'm now using v2.6.1 of Kip's plugin. The big (and wonderful) improvement in this version is that the plugin will now never expire a cached Gravatar unless gravatar.com provides a new image. This means there will never be a gap caused by cache expiration.