Flex Interval Timer

Flex Interval Timer is a highly flexible interval timer designed for any kind of training — weight training, HIIT, stretching, and more.

> Combine Phases Freely

Build your sessions with phases like Warm-Up, Work, Rest, and Cool-Down - in any order and duration you choose.

> Loop Settings

Group phases into loops to handle complex interval patterns with ease. Perfect for Tabata, circuit training, and more.

> Countdown to Stay Ready

A countdown before the start and before each phase ends keeps you prepared for what's coming next.

> Audio Cues for Timing

Sound effects notify you at every phase transition so you never lose track.

> Customize Phase Names

Rename phases in the menu to match your own training style.

> Track Your Training History

Review completed sessions in a calendar view to stay motivated and consistent.

> Save Presets for Quick Start

Save your favorite routines as presets and launch them in one tap next time.

> Dark / Light theme support

> Available in Japanese and English