Things to consider
With the required amount of money, you can buy just about anything, but it will not be the best fixed gear bike if it is not chosen as per the fundamental requirements of cycling, and more importantly, your preferences.
So, here are the considerations you need to make before paying for the best fixed gear bike.
This should always be the first question when buying any sort of bike, but triply so for a fixed gear. For starters, have you ever actually ridden a fixed gear before? Do you know how different it is from a "regular" bike? If the answer to those two questions is "no," definitely look into something with a flip-flop rear hub (fixed on one side, freewheel on the other) and brakes, so you're not dictating a Craigslist "For Sale" ad from your hospital bed the following week.
Finding a fixed gear under $500 is easy enough, but so is finding one for a hell of a lot more. And it is not just a matter of how much can you spend, but how much do you want to spend. Will you be locking it up outside a lot, or commuting from apartment to office? A lockup bike-especially in a big city-should be considered more or less disposable, so spend accordingly.
From all-black to chrome to "bag of Skittles," there are as many color options as there are price points. Just one manufacturer-say, Mott Street Cycles-offers damn near the full Pantone book of options. Again, what you will be doing with the bike should play into what look you go for. All-black might not reflect your personality, but it also might make it less attractive to would-be thieves.
Geometry is different than sizing, which is equally important. Fixed gears are derived from track bikes, which were made to be ridden in circles very fast. Hence, a true track bike might not be the best choice for a daily rider. Track bikes have super-tight geometry, which means a short wheelbase and lots of toe-over-turn the wheel hard, and it's probably going to crash into your foot, which will hurt a lot. More street-worthy bikes have more relaxed angles, lessening the chances of accidental death and dismemberment.
Once the whole geometry thing is sorted out, size is next. Generally speaking, it is good to size down from one's road bike size (so, if you ride a 57, get a 55). If none of this makes a lick of sense, get to a bike shop and test ride some bikes. Ordering a fixed gear online without ever riding anything is a good way to get catfished. Do not just guess.
We addressed this earlier, but a fixed gear can be so much more than just a commuter. Are you going to race it? Play bike polo (no, seriously)? Be a messenger? Do tricks? Stunt on Fixed Gear Gallery? All of the above? The way you answer this question will change your options dramatically. There's no point in getting a handmade frame if its destiny is to be getting locked to parking meters and whacked with mallets.
Not many choices here, really, and no need to get a degree in metallurgy to understand. Carbon fiber, no. Aluminum will rattle you to pieces and get dented in a hurry. Hi-ten steel is cheap, but you get what you pay for. Ideally just stick to chromoly steel, whether from a "name" company like Reynolds or True Temper or no-name. A good frame should last you forever. Then again, hi-ten is fine for a lockup ride.
The parts on a bike are important, but not nearly as important as the frameset. Upgrading is a way of life for anyone into bikes, and most components should be replaced as they wear regardless. The most important parts to consider starting out is the wheelset, and as long as the hubs are sealed and the hoops are alloy, good enough. Saddle and pedals are a matter of personal preference and should probably be swapped out right away no matter what comes stock.
It doesn't really matter so much anymore, seeing that so much manufacturing has been outsourced nowadays, but there's still something timelessly cool about, say, a Celeste green Bianchi. That heritage will come with a cost, but hey, sometimes, it’s worth it. Up to you. If bicycle history means nothing to you, though, feel free to head straight to Bikes Direct.
And we come full circle. There is no need to get a full physical workup from an orthopedist before buying a fixed gear (although it would not hurt), but still, consider all the ramifications of this purchase. Do you really want to ride a fixed gear, or is this a purchase destined to become a rather esoteric-looking coat rack? Try someone else's bike before you buy your own.
We know you have got a lot in your mind after reading what we have tried to inform you of the best fixed gear bike. Too much information, nah?
Choosing any of the above fixie bikes does not necessarily indicate that you have to be confined to what these bikes have to offer. With a little money and knowledge about the right accessories, you can easily turn the best value fixed gear bikes into the best custom fixed gear bikes.
The final piece of advice for you is that you prioritize your riding skills, budget, intended terrains, and other preferences. Only then, you can get the best fixed gear bike that helps you take your road riding to the desired level.