Nothing Is Faster

Interval Timing. Instantly.

Build your custom interval timer in under a second. Hold. Speak. Train. Nothing is faster.

Hold
Press and hold the button
Speak
"5 rounds, 3 minutes, 1 minute rest"
Train
Timer is running. Go.
Total time to start
<1 second
<1s
Setup Time
0
Menus to Navigate
0
Fields to Fill
1
Button

Every other timer
wastes your time

Other apps make you tap through menus, scroll through settings, and fiddle with numbers. RoundBoss doesn't.

Other Timer Apps
  • Open app, find the right screen
  • Scroll through settings menus
  • Manually set rounds, work time, rest time
  • Tap through number pickers
  • Finally press start
30-60s
Average setup time
RoundBoss
  • Hold one button
  • Say what you want
  • Training starts instantly
<1s
Total setup time

Fast doesn't mean
stripped down

Speed is the starting point. Everything else you'd expect from a premium timer is built in.

AI Voice Parsing

Say anything natural. "Boxing 12 rounds" or "Tabata 8 sets 20 on 10 off." AI figures it out instantly.

Precision Engine

Timestamp-based timer with 100ms accuracy. Prep, round, warning, and rest phases with distinct audio cues.

Template Library

Presets for Boxing, MMA, HIIT, Tabata, and more. Tap once and go, or save your own custom templates.

Sound Themes

17 sound themes from voice coaches to pure SFX. Wooden block, zen garden, military drill, arcade — pick your vibe.

Haptic Feedback

Feel every phase change through your phone. Round starts pulse, warnings tap, rest periods breathe. Eyes-free training.

Premium Themes

Six visual themes from Boss Mode to Deep Ocean to Ice Storm. Each with its own color palette and personality.

Hold. Speak. Train.

The world's fastest way to start a custom interval timer.

01

Hold the Button

One button. Center of the screen. Press and hold — voice recognition starts immediately.

Instant
02

Say Your Workout

"5 rounds, 3 minutes each, 1 minute rest." Natural language. AI parses it in real time.

~2 seconds
03

Timer Is Running

Release the button. Review your setup, tap Start, and you're training. Or quick-start skips straight to the timer.

Instant

Built for speed.
Designed for athletes.

Every screen, every interaction — engineered to get out of your way and let you train.

Speak Your Workout
"5 rounds, 3 minutes, 1 minute rest"
Hold to talk
Round 3
1:47
of 5 rounds
Library
Your Templates
Morning
4 rds
Heavy Bag
10 rds
Sparring
6 rds
Cardio
8 rds
Boxing & Combat
Pro Boxing
12 rds
MMA Fight
5 rds
Muay Thai
5 rds
Kickbox
8 rds
HIIT & Tabata
Tabata
8 rds
HIIT Burn
6 rds
Circuit
10 rds
Endurance
15 rds

Stop setting up.
Start training.

Free to download. Voice setup in under one second. No ads, ever.