When I asked Pyra Labs' Evan Williams the same question (again by email), he also didn't know the answer off-hand. "We figure the branding/word-of-mouth effects are probably worth the extra cost of super-popular blogs," he wrote. "In the case of InstaPundit, that's definitely the case, as he's caused a ton of others to start their own blogs (and also pay the $12). (I haven't looked at how much [bandwidth] his blog is taking. Sorry.)"

Without actual statistics from Reynolds and Williams, I decided I would simply try to estimate how much bandwidth Instapundit.com uses. When I asked Reynolds how many pages Instapundit.com serves on a daily basis, he replied that the number was in the "low-to-mid 20Ks during the week, and about half that on weekends." For the purposes of my estimate, I used "20,000" as the average number of pages Instapundit.com serves a day. (He recently announced that he had reached a new high of 30,502.) Because Reynolds posts so frequently, Instapundit.com pages grow fairly large even though they're mostly text. Usually, they're at least 150K, but to keep the math extra-simple, I used 100K as the average file size of a page. And, thus, I arrived at the 2 GB a day estimate (100K times 20,000 pages equals 2,000,000K, or 2GB).

In addition to the somewhat imprecise nature of the numbers I chose, this estimate doesn't take into account any caching that might reduce the amount of bandwidth that Instapundit.com transfers. In a second email that I sent to Evan Williams, I asked about the ways in which caching may affect Blogger data transfer, but he has not yet replied. (On January 25th, Williams made Blogger Pro available [more on this below], so I imagine he is extremely busy dealing with that and hasn't had much time lately for answering email.)

For those who are wondering how Pyra Labs can offer web-hosting services for so much less than other web-hosts do, part of the answer lies in the fact that blogspot.com has certain limitations. As Williams explains it, "The reason it works at such cheap prices is because we don't offer the image (/movie/mp3) hosting. So it's really hard for a single blog to use much bandwidth…" In other words, if you use blogspot.com, you pretty much have to stick to a text-centric approach to web publishing. In addition, there are various other tools/services that most traditional web-hosts provide that blogspot.com doesn't offer: by keeping things simple, Pyra is able to offer a valuable core service - text-oriented web-publishing - for an extremely reasonable price.

Bloggers who host their sites on blogspot.com also benefit from the fact that instead of purchasing bandwidth at a flat rate (i.e., $3 per GB), Pyra Labs appears to lease a "fixed pipe" from Exodus. I say "appears" because I didn't wholly understand the answer Williams gave when I asked him how much Pyra Labs spends on blogspot.com bandwidth each month. In reply to my query about this, he wrote, "Last I checked, Blog*Spot was costing us approx. $500/month in bandwidth, which is about .5MBps, on average."

As I understand it, there are essentially two ways web-hosts sell bandwidth: at a flat rate, or by capacity. In the first scenario, the web-host tracks exactly how much data you transfer each month and charges you a flat rate for each GB. In other words, if your rate is $3 per GB, you pay $30 if you use 10 GB and $300 if you use 100 GB. In the second scenario, you lease a line (or "fixed pipe") that is capable of transferring X number of megabytes per second, for a single monthly fee. In this scenario, it doesn't matter if you transfer 10 GB a month or 1000 GB a month, the price you pay will be the same. But because the pipe is "fixed," there is ultimately a limit to how much data you can transfer in a month, or more specifically, in a second: if you've leased only one fixed pipe and your site starts getting more visitors than that pipe can accommodate, visitors will not be able to access your site.

What confused me about Williams' reply are the words "approximately" and "on average." I.E., I'm not sure why he would uses those words/phrases if he's paying a specific amount of money for a line that has a specific fixed capacity. My guess is that Pyra leases multiple fixed pipes, and that one of those fixed pipes (a .5MBps connection that costs $500 a month) is generally enough to handle blogspot.com's traffic, but that maybe sometimes a portion of another pipe is needed as well. (I've asked about this in a follow-up email, and if Williams provides clarification, I will include it here.)

In any case, what follows is an attempt to estimate how much the bandwidth that Instapundit.com uses each month actually costs Pyra Labs…

If Pyra Labs generally requires .5MBps capacity to accommodate blogspot.com's bandwidth demands, that means that the total amount of data blogspot.com can transfer in a 30-day month is 1296 GB. (.5MB x 60 seconds x 60 minutes x 24 hours x 30 days = 1296000 MB, or 1296 GB.)

And if Pyra Labs is paying approximately $500 a month for that bandwidth, that means that it spends 38 cents for each GB ($500 / 1296 GB).

Thus, if Instapundit.com uses 60 GB of bandwidth each month, Reynolds is actually getting $22.80 worth of bandwidth from Pyra Labs for the $1 he pays each month. (As I noted elsewhere, Reynolds now pays $35 a year to use Blogger Pro. But theoretically, at least [I'm not sure how Williams views it], that payment has nothing to do with the blogspot.com service that Reynolds purchases as well. That is, a Blogger Pro subscription covers the costs of developing and maintaing the Blogger Pro code and maintaining the server that runs the Blogger Pro software. And, thus, for the blogspot.com bandwidth that Instapundit.com uses, Reynolds is still just paying $1 a month.)

Given that Williams says that a lot of bloggers have established blogs on blogspot.com because of Reynolds, it may in fact be true that it's worth it to Pyra to subsidize Reynolds' blog in this way - especially if most of the bloggers Reynolds has brought to blogspot.com use less than $1 worth of bandwidth each month.

And in addition, of course, $22.80 a month is a fairly trivial sum of money. But hopefully the main point I'm trying to make here is clear: Reynolds and all the other bloggers who host on blogspot.com derive their fiscal efficiency in large part because of the efforts of one unusually generous individual, Evan Williams, who charges much less for the services he provides than probably 99.9% of the commercial web-hosting operations out there. And if Williams decides he's no longer interested in maintaining Blogger and blogspot.com, or if he can't make these endeavours work financially, what happens? Reynolds and all the other bloggers who use blogspot.com and Blogger will have to seek other hosting/software solutions, which will likely cost much more, because there aren't that many people around who are willing to offer what Williams offers so cheaply.

Of course, Williams isn't the only person who can lease a "fixed pipe" line from a web-host and thus benefit from the much better price per GB of bandwidth transfer that such a deal affords. Indeed, if Reynolds wanted, he could lease a fixed pipe himself, if he were willing to spend a minimum of at least a few hundred bucks a month. In addition, Reynolds and various other bloggers might band together to lease a fixed pipe. To do this, however, they'd still need someone coordinating their efforts, setting up and maintaining their server - someone like Williams, that is.

While Williams seems driven in large part by motivations that have nothing to do with money, at the end of the day he must believe that Blogger and blogspot.com are built upon a workable business model. And indeed, in our email exchange, he stated the following: "Blog*Spot pays for itself (and then some) via the $12 ad-free payments. (Advertising was doing okay, too, until last month.)"

But as the case of Reynolds shows, the ad-free portion of the blogspot.com business model works only as long as (a) blogspot.com bloggers don't post that often, and (b) blogspot.com bloggers don't attract many readers. Indeed, as soon as an ad-free blogspot.com blogger starts serving 1000 100K pages a day, that blogger is theoretically costing Williams 14 cents a month.

The point: bandwidth costs money, and servers cost money, and the people who maintain the servers deserve money for their efforts. And such costs must be factored into any reasonable evaluation of how financially efficient weblogging is.

To a certain extent, Reynolds seems to be aware of this. He has urged other bloggers to pay the $12 blogspot.com ad-removal fee as he did, and in a recent email exchange, he exclaimed, "I would be willing to pay more, and although I've taken some steps toward possibly moving off of Blogger/Blogspot if it goes down, I'd prefer to stay. I'm hoping that the Blogger Premium service I keep hearing about will make that possible."

And now that Pyra has introduced Blogger Pro, he has put his money (or at least $35 of it) where his mouth is. But Reynolds seems somewhat disenchanted by these new fees, even though they are still remarkably reasonable. "THERE IS NOW A PAID, MORE-FUNCTIONAL VERSION OF BLOGGER and I'm going to switch to it shortly," he posted to Instapundit.com on January 27th. "I'm holding off today, because I'm seeing a lot of emails that people who sign up are having trouble getting registered, but I expect that will be fixed shortly. The bummer is, it's priced in part by the volume of postings -- which, as you might imagine, hits me pretty hard. But I'll do it anyway." When Reynolds did do it later that day, he wrote, "The signup's not bad, but I'll be paying through the nose for posting bandwidth. (This won't affect most people who are, ah, less prolific posters than me). Oh, well -- the Amazon tipjar will cover it. And I've been trying to funnel money to Blogger for a while, so I don't really mind paying. Heck, even with the bandwidth charge, it'll be less than I've been spending buying off people's Blogspot ads."

Hits him pretty hard? Paying through the nose? With Reynolds evangelizing in such enthusiastic fashion, perhaps Pyra Labs will scrape together enough revenues to continue offering the services it offers. But in the end, of course, you get what you pay for. Because the bloggers who use Blogger and blogspot.com haven't been adequately funding these services to date, these services haven't been completely reliable. "TRAFFIC BROKE THE HALF-MILLION MARK THIS MORNING: I just couldn't post on it because Blogger was down," Reynolds wrote on November 11, 2001. "BLOGGER IS STILL NOT WORKING RIGHT, though Ev is promising a fix soon," Reynolds wrote on January 9th, 2002. "Just remember: if this setup craters, I'll have the InstaPundit.Com address directed to the new site as soon as that's clear."