Numbers flash on the screen
A sequence appears one number at a time, each lasting only a fraction of a second.
The Viral Flashing Numbers Explained
What Was James Charles Doing With the Flashing Numbers?
He was using Flash Anzan—a mental math exercise that trains people to visualize and add numbers at high speed.
Those rapidly flashing numbers are part of a real mental math training method. The challenge is to visualize each number, keep a running total, and enter the final sum.
SumoMath is not affiliated with or endorsed by James Charles. We were surprised to see our Flash Anzan software appear in his video.
The method
What is Flash Anzan?
Flash Anzan is a mental calculation exercise in which numbers appear one after another for a short period of time. The participant mentally adds them and enters the total.
Trained users often visualize a soroban, or Japanese abacus, in their minds—moving imaginary beads as each number flashes by. With practice, the mental image becomes clear enough to keep a running total at remarkable speed.
Visualize and add
Learners picture each value—often on a mental soroban—and keep a running total.
Enter the final answer
When the sequence ends, the participant submits the sum and checks their accuracy.
The technique
Why was he moving his fingers?
Those finger movements follow the SumoMath progression: learners first manipulate beads on a physical soroban, then visualize those same movements as mental images, and finally calculate entirely in their heads.
Experienced soroban and mental math users sometimes still move their fingers while calculating. The motions imitate sliding beads on an abacus and help keep that mental image clear—even when no physical tool is in front of them.
James Charles may have been doing this playfully or for dramatic effect—but the underlying technique is real. Similar finger movements are genuinely used by trained mental math competitors.
Skill building
Can people really calculate this fast?
Fast mental calculation is a learned skill. Students begin slowly with a physical or digital soroban, develop accurate bead movements, and gradually learn to visualize the abacus without seeing it.
Learn the bead movements
Master how each digit is represented by sliding beads on a physical or digital soroban.
Build a mental image
Practice until you can “see” the abacus clearly in your mind and update it as numbers appear.
Increase speed gradually
Shorten flash intervals and raise digit ranges step by step—progress comes from deliberate practice, not unusual talent.
The platform
About SumoMath
SumoMath helps students develop arithmetic fluency, number sense, concentration, and mental visualization through structured soroban and mental math training.
Flash Anzan is one of many tools in the SumoMath ecosystem—designed to make high-speed mental calculation approachable and fun.
- At home for independent practice
- In schools and classrooms
- In microschools and learning pods
- In dedicated mental math programs
Think You Can Keep Up With the Flashing Numbers?
Build the same mental math skills with SumoMath’s structured soroban and Flash Anzan training.
Questions
Frequently asked questions
James Charles recently used SumoMath’s Flash Anzan tool in a social media video. SumoMath is a visual and mental math platform based on soroban training. There is no official partnership or endorsement.
Flash Anzan is a mental calculation exercise in which numbers appear one after another for a short period of time. The participant mentally adds them and enters the total. Trained users often visualize a soroban in their minds.
Experienced soroban and mental math users sometimes move their fingers while calculating. These movements can imitate sliding beads on a physical abacus and help maintain a clear mental image of the calculation.
Yes. Flash Anzan is a recognized mental math activity practiced by students and competitors who train with the soroban and mental visualization methods.
Yes. Children can learn Flash Anzan through progressive training—starting slowly, building accurate bead movements, and gradually increasing speed as their mental visualization improves.
No. James Charles is not currently affiliated with or endorsing SumoMath. He independently used the Flash Anzan tool in his video.