The 40-yard dash has to be one of the revered athletic metrics in sports. Truth be told, it’s not even that meaningful of a metric. Historically speaking, there have been a ton of NFL busts over the years who posted some of the most impressive 40-yard dash times in NFL history, only to enter the league and fail to do anything else memorable. So why do we care so much about the 40-yard dash? Well, to be fair, it is a great way to measure how fast someone can move once the ball is snapped. However, the mystique of the 40-yard dash has much more to do with the simplicity of the metric. Watching an athlete run those 40 yards as fast as they can never cease to be an impressive visual. It’s why 40-yard dash times are so closely associated with a player’s athletic potential.

However, 40-yard dash times in the NFL are more complicated than they used to be. Not long ago, the NFL decided to start measuring 40-yard dash times with a digital timer. Before then, many scouts and officials relied on timing the runs via handheld stopwatches. This change meant that some of the old, non-digital 40-yard dash times of the past became unofficial. Only the runs of the digital era are recognized as “official” times. Still, there are a lot of “unofficial” 40-yard dash times that should never be forgotten. These are the official 10 fastest 40-yard dash times in NFL history (and 10 fastest unofficial times).

20 Official: Jacoby Ford - 4.28 Seconds

If you’re a wide receiver that gets drafted by the Oakland Raiders, you must be fast, especially if it was back in the days of Al Davis running the team.

For years, the Raiders valued speed in their receivers above all other attributes.

It almost never worked out for them, but they did snatch some of the fastest official players in NFL history. Jacoby Ford easily ranks among the fastest players in that group. His NFL career was a true bust, but his 40 time of 4.28 was a jaw-dropping accomplishment that even some of the fastest receivers in NFL history can only gawk at.

19 Unofficial: Deion Sanders - 4.21 Seconds

We all know that Deion Sanders is fast. Just about any piece of footage from his career reveals that the guy possesses some breakaway speed. Sanders’ speed is legendary, as was his ability to turn that speed into a weapon on any given play. Exactly how fast is Sanders, though? Well, his legendary NFL Combine performance saw him run an official 4.27.

That’s fast, but it still doesn’t beat those stories that say Sanders was clocking an unofficial 4.21 around that same time. It’s far from unreasonable that Sanders might have hit that time, so don’t dismiss this one outright.

18 Official: J.J. Nelson - 4.28 Seconds

As the years go on, NFL scouts are seemingly becoming more and more wary of speedy receivers. The fact of the matter is that too many teams have gotten burned in the past wasting high draft picks on pure speed, while overlooking route running or hands. However, that also means that guys like J.J. Nelson can fly a little under the radar. Nelson is quickly becoming quite the weapon for the Arizona Cardinals. That probably doesn’t come as too much of a surprise to those who watched his Combine performance. After all, an official 4.28 is NFL lightning.

17 Unofficial: Randy Moss - 4.20 Seconds

Here’s another case of the NFL’s “official” records kind of mess with the overall rankings of players. We know that Randy Moss recorded a 4.25 40-yard dash at the 1998 NFL Combine. There are records and witnesses that say so. However, due to the new NFL rules, his old time isn’t recognized as one of the all-time fastest.

What’s really interesting, though, is that his insane NFL time may not have been his fastest 40.

Multiple reports suggest that Moss clocked a 4.20 - 4.21 40 in college and in his days leading up to the NFL Draft.

16 Official: Jalen Myrick - 4.28 Seconds

Receivers and running backs are the most famous sources of pure speed in the NFL, but cornerbacks can easily be the absolute fastest guys on the field. They may not have the hands of receivers or their route running abilities, but that doesn’t mean they aren’t blazing fast. It's probably why they're moved to corner in the first place. Among the fastest modern NFL cornerbacks is Jaguars defender Jalen Myrick. It remains to be seen whether or not Myrick has the full range of talents needed to really make it in the NFL, but his 4.22 40-yard dash time confirms he’s at least got the speed.

15 Unofficial: Darrell Green - 4.20 Seconds (At Age 40)

Darrell Green is one of the absolute fastest men to ever play in the NFL. His speed is legendary among those who saw it. Sadly, he’s another guy whose era keeps him out of the running for an official NFL 40-yard dash time. So far as that goes, there have long been rumors of Green clocking a 4.15 in his prime. What we can tell you with a little more certainty, though, is that Green ran a 4.20...at the age of 40. Yes, shortly after signing a new NFL contract, Green ran an unofficial 4.20 40 at the age of 40.

14 Official: Tyrone Calico - 4.27 Seconds

Tyrone Calico is a strange case. Given that he was drafted in the second round of the 2003 NFL Draft, you’d think that he would have had an exceptional college career. However, his Middle Tennessee State stats really aren’t that amazing.

The one thing that Calico had that some teams felt they could take advantage of was pure speed.

In fact, the NFL has him listed as running a 4.27 40-yard dash at the Combine. However, other figures suggest he more commonly ran between a 4.34-4.40. Like so many other speedy receivers out of college, Calico didn't achieve much of note.

13 Unofficial: Terrell Sinkfield - 4.19 Seconds

Don’t know the name Terrell Sinkfield? There’s a very good reason for that. While he bounced around the NFL for a few years, he was cut by every team that gave this cornerback a chance. You may wondering why so many teams took a chance on an undrafted cornerback. The reason might have something to do with the 4.19 40-yard dash that Sinkfield ran. While he didn’t post that time at the NFL Combine, he did record that figure at Minnesota’s Pro Day tryouts. Sadly, that isn’t good enough for the record books. And his NFL career has yet to really take off.

12 Official: Stanford Routt - 4.27 Seconds

Here’s another one of those fast players that we really can’t blame the Oakland Raiders for drafting despite the team’s awful history of drafting fast NFL players. At Houston, Routt’s speed turned him into an absolute weapon. However, it was on the track that Routt shined as one of the fastest college athletes you ever will see. Oakland spent a second-round pick on Routt, but he never really proved to be an effective NFL cornerback.

Still, Routt’s 4.27 has to be worth something even if that something isn’t a high draft pick. It's unfortunate that Routt couldn't put it all together.

11 Unofficial: John Franklin III - 4.19 Seconds

Some of you might remember John Franklin III from his appearance on Netflix’s Last Chance U. He was the clearly talented athletic QB who was able to make the best of a rough situation and eventually be picked up by Auburn on his way to an NFL contract.

Somewhere along the way, he supposedly ran an unofficial (by NFL standards) 40 time of 4.19.

Given how many reports of that time that we’ve heard from pretty official sources, we’re willing to bet that Franklin did hit that insane mark. We'll see if he ever gets to run an official 40 at an NFL combine.

10 Official: Marquise Goodwin - 4.27 Seconds

Like many of the fastest men in the NFL, Marquise Goodwin was also a track star in college. Actually, he made the United States Olympic team as a long jumper. If someone could have made a lucrative career off long jumping, Goodwin might have done so. As an NFL player, though, he shocked those in attendance at the NFL Combine by posting a 4.27 40-yard dash.

Scouts knew Goodwin had legs, but his Combine performance made scouts consider the possibility that he might be more than an NFL novelty. It remains to be seen if he will prove himself.

9 Unofficial: Joey Galloway - 4.18 Seconds

Joey Galloway was essentially human lightning during his time in the NFL. There’s an argument to be made regarding whether or not his up-and-down performances made him worthy of the top 10 draft pick the Seahawks spent on him. What you can’t argue against is that Galloway was a scary player when he was playing at the peak of his game.

Before the NFL implemented their rules regarding digital 40-yard dash times, Galloway recorded an astonishing 4.18 time. It sounds absurd, but we’re not entirely sure it wouldn’t hold up in the digital era. If only the technology was available back then.

8 Official: Jerome Mathis - 4.26 Seconds

If you really want to be impressed by Jerome Mathis’ speed, go look at some of his High School track records.

As a young man, he ran the 100 meter dash in 10.49 seconds. For comparison’s sake, Usain Bolt ran the 100 in 9.58.

In college, he set a record for kick return average. At the NFL Combine, he achieved what was then the second fastest official 40 time in NFL history by running it in just 4.26 seconds. Sadly, he never turned into anything more than a mediocre NFL player. Surprisingly, it didn't even lead to a successful run in track and field.

7 Unofficial: Alexander Wright - 4.13 Seconds

Alexander Wright wasn’t a great receiver. He wasn’t the worst receiver that you’ve ever seen, but don’t feel too bad if you haven’t heard his name. In fact, the only thing that you really need to know Alexander Wright is that he was fast. We mean scary fast. At the University of Auburn, he tied Bo Jackson’s sprint times. He was the two time winner of the NFL’s fastest man award. He posted an unofficial 4.13 40-yard dash time. The run in question apparently took place in 1991, which is sadly not close to the NFL’s recognized timeline for official records.

6 Official: Dri Archer - 4.26 Seconds

Here we have yet another NFL bust who is most famous for his 40-yard dash time. Are you starting to notice a pattern here? We're just surprised that he wasn't a draft pick of the Raiders. When Dri Archer came out of Kent State, some NFL scouts believed that his incredible breakaway speed might just be good enough to make up for his other deficiencies. He was the kind of raw talent that some NFL teams think they can mold into greatness. It didn’t hurt that he posted a 4.26 40-yard dash time. Sadly, Archer never panned out as an NFL pro.

5 Unofficial: Bo Jackson - 4.13 Seconds

You’ve probably been waiting for this one. First off, in case you don’t know, it’s a little difficult to separate truth from fiction when it comes to Bo Jackson.

What we can tell you for sure is that he’s one of the most talented all-around professional athletes of all-time.

Because of that, people tend to believe a lot of crazy stories about him because so many other crazy stories are true. So did Jackson really run a 4.13 40-yard dash? Actually, he did. It was even digitally timed. Apparently, he also ran a 4.12 that was timed by hand.

4 Official: Chris Johnson - 4.24 Seconds

You probably know about this one. Truth be told, Chris Johnson wasn’t a highly-touted NFL prospect. It was thought that he might go in the second round, but he wasn’t seen as a top guy. However, Johnson certainly turned some heads at the NFL Combine when he posted a 4.24 40-yard dash time. Unlike some of the other players on this list, Johnson actually proved to be a pretty good NFL player. While he never replicated his 2,000 rushing yard season, he was an effective starter throughout his time in Tennessee.

3 Unofficial: Christian Coleman - 4.12 Seconds

This one is going to be controversial for a few reasons. First off, Christian Coleman is not actually a football player. He’s a track and field sprinter. Actually, he’s an incredible track and field sprinter.

He’s an unbelievably fast human being that has proven his merits at the Olympics.

He also took the time to replicate the conditions that NFL prospects run their 40-yard dash in (turf, cleats, etc.) to see how fast he could complete the run. He completed it in just 4.12 seconds. There’s video proof of this one, so there’s no arguing it.

2 Official: John Ross - 4.22 Seconds

To reiterate, the reason that the NFL uses digital times as part of the “official” records is that the difference between digital and hand recordings can be drastic. However, if you manage to post anything below a 4.30 according to the digital times, then you are an absurdly fast human being. That means that John Ross is an absurdly fast human being. Already seen as a top receiving prospect coming out of college, the 4.22 40-yard dash time that Ross posted as the NFL Combine secured his top-10 draft pick status. Now all he has to do is make sure that's not the only thing he's remembered for.

1 Unofficial: Jakeem Grant - 4.10 Seconds

This one is about as unofficial as they come...but it’s an utterly fascinating story. At Texas Tech, Jakeem Grant posted one exceptional season (over 1,200 receiving yards) and a few less-than-exceptional seasons. He wasn’t seen as a can’t miss, must-have prospect. While Grant skipped the combine, he did run a 4.34 40-yard dash at Texas Tech’s pro day. However, a New Orleans Saints scout that was watching run claims that he clocked him at 4.10 during one of his runs. While that recording was done by hand - and wasn’t listed at the official time - it’s certainly worth mentioning.