How Fast Can The Flash Run? Barry's Snyder Cut Powers Explained
The Justice League Snyder Cut confirms that Barry Allen's powers don't depend solely on speed. He's how The Flash's DCEU superpowers work.
Zack Snyder's Justice League confirms that Ezra Miller's Barry Allen is one of the fastest versions of the Flash despite being inexperienced with the DCEU's Speed Force. Up until the release of the Justice League Snyder Cut, the Flash counts with three different DCEU appearances, one Arrowverse cameo, and one solo movie in the works. Before he gets to learn about the true extent of his powers in The Flash, Barry Allen only knows that he can tap into a mysterious source of super speed to move incredibly fast. Despite being oblivious to the potential this ability holds, Barry Allen is already able to break the sound barrier and make small jumps back in time.
The Flash's powers let him defeat villains like Captain Boomerang and the Parademons effortlessly, but they can help him achieve much more than that. In the comics and in the Arrowverse, where he has experimented with the Speed Force for a much longer time, Barry Allen can use his speed to acquire secondary abilities like creating wind vortexes, phasing through solid matter, and most famously, traveling through time. Barry Allen is usually so fast that his fights against villains like Gorilla Grodd and Darkseid aren't a question of speed but of strategy, since he's clearly much faster than most DC characters.
The Flash is often tasked with the critical decision of rebooting the whole multiverse, and the way he does it is by running as fast as metahumanly possible. In the DCEU, Barry Allen only demonstrates a fraction of this power, but he's still quite fast by speedster standards. Here's how fast the Flash is in the Justice League Snyder Cut and how his superpowers work.
Although the DCEU hasn't given a solid explanation for The Flash's powers, the existence of the DCEU's Multiverse suggests that he got them the same way as all the other multiversal versions of himself, which is through a bolt of lightning that struck him and linked him to the Speed Force. When the Flash taps into the Speed Force, he can run at tremendous speeds without any negative effects besides an increased appetite and accelerated metabolism. External effects include lightning bolts wrapping around his body and the added responsibility of being extremely careful with whatever he touches when he's moving.
The Justice League Snyder Cut also reveals that regular shoes explode as soon as he moves his feet at superhuman speeds, and despite being able to save Iris West in the middle of a high-speed car crash, Barry Allen must move her very carefully to avoid harming her with friction or inertia. The Flash's costume uses special materials for this reason, as he needs to be as aerodynamic as possible when running, although it seems that he doesn't have to strain his body to run faster. Instead, the Speed Force appears to dictate how much energy he uses and how fast he goes instead of his physical condition, as evidenced by the way the Flash moves his arms and feet so slowly and awkwardly while running. If his speed depended solely on his physical effort, he would need to move his body — especially his extremities — at a much faster rate.
The Flash's speed in the DCEU varies greatly, but it is so great that it makes time appear almost frozen. The first clue to Barry Allen's superspeed came in Batman v Superman: Dawn of Justice, where security footage showed Barry Allen stopping a robbery in a matter of nanoseconds. At this point, Barry is fast enough to run across a grocery store and back without the camera noticing his movement. The Snyder Cut shows that the Flash's speed is enough to obliterate his shoes with only a turn of his feet, and enough to let him catch Iris West in midair before her car lands following a fiery crash (while also fondling her hair and stealing a sausage in the process), and even before the shards of glass from a window he shattered several feet away can hit the floor.
Flash's Time Travel Explains Why He's Snyder Cut's Most Changed Hero
All of this puts the Flash's DCEU regular speed at several hundred miles per hour. His speed doesn't cause an explosion after breaking the sound barrier, but that can be chalked up to the effects of the Speed Force. While the DCEU hasn't shown the Flash's top speed, it has revealed that he can travel back in time using the Speed Force. In real life, time really does appear to behave differently at the speed of light, which moves at approximately 300,000 kilometers per second (186,000 miles per second), but there's no real evidence that light can actually travel back in time. Hence, The Flash's superhuman time travel ability may be a different power altogether rather than sheer speed.
Although time travel doesn't seem to be the next direct stage from superspeed, The Flash does appear to make a big effort in order to go back only a few seconds during the fight against Darkseid in the Justice League Snyder Cut. Barry Allen is allegedly able to time travel a few years back using the Cosmic Treadmill, which lets him travel from the not-so-distant future of the Knightmare scenario back to the events of Batman v Superman: Dawn of Justice, where he warns Bruce Wayne that "Lois is the Key" to keep Superman from succumbing to Darkseid's Anti-Life Equation. This device helps the Flash travel through time and space more accurately (though not more stably, as his appearance in Batman v Superman: Dawn of Justice suggests). Without it, the Justice League Snyder Cut reveals that The Flash can time travel by himself, but only short timespans and by mere intuition.
The Speed Force is inherently linked to the act of running, but it's also associated with time, space, and the fabric of reality. The Flash's connection to the Speed Force lets him run extremely fast and travel through time, which in turn can open doors to different realities and break the Multiverse wide open. The comics and the Arrowverse have found various ways to explain the Speed Force realistically. Now that Zack Snyder's Justice League has set the basis, it's the turn of Andy Muschietti's The Flash to delve into the intricacies of the Flash's powers in the DCEU.