4 x 4 Exercise Timer

Perfect for interval training and workout routines

Duration (Minutes)

Duration (Seconds)

Repetitions

Rest Time (Optional)

Rest Minutes

Rest Seconds

Leave both at 0 for continuous intervals without rest periods.

WORK TIME

04:00

Interval 1 of 4

Total Time: 32:00

🔊 Enable sound for audio alerts on mobile devices

How to Use Exercise Timer

Set Work Duration: Choose your exercise duration between 10 seconds and 30 minutes using the work time inputs.

Set Rest Duration (Optional): Add rest time between intervals for HIIT workouts. Leave at 0 for continuous intervals.

Set Repetitions: Choose how many intervals you want to complete (1-30 repetitions).

Start Timer: Click the Start button to begin. The timer will alternate between work (green) and rest (blue) phases.

Sound Alerts: A 1-second alarm will sound at the end of each work and rest phase. Click "Enable Sound" for mobile audio, which includes vibration fallback. Use the sound button to mute/unmute.

Controls: Pause to take a break, or reset to start over. Your settings are automatically saved.

Sleep Mode Fix: Timer now continues accurately even when your phone goes to sleep! The ⚡ button keeps your screen awake (shows ON/OFF and turns green when active).

Mobile Features: Includes vibration alerts when sound fails, Web Audio API for better mobile compatibility, and Service Worker for background timer continuation.

Perfect Exercise Examples

Endurance Intervals

Long-form aerobic and anaerobic training

• 4 minutes intense work, 4 minutes active recovery
• 4 rounds (32 minutes total)

HIIT Workouts

High-Intensity Interval Training with work/rest cycles

• 45 seconds work, 15 seconds rest
• 8-12 repetitions per workout

Tabata Training

Classic 4-minute high-intensity protocol

• 20 seconds intense exercise, 10 seconds rest
• 8 rounds (4 minutes total)

Circuit Training

Move between different exercise stations

• 60 seconds per station
• 6-10 different exercises

Boxing Rounds

Traditional boxing training intervals

• 3 minutes work rounds
• 3-12 rounds per session

Yoga & Stretching

Hold poses for specific durations

• 30-60 seconds per pose
• 5-15 different poses

Strength Supersets

Back-to-back exercises without rest

• 45-60 seconds per exercise
• 4-8 supersets

Cardio Intervals

Alternate between high and low intensity

• 2-4 minutes high intensity
• 5-10 intervals

Calisthenics

Bodyweight exercises with timed sets

• 30-90 seconds per exercise
• 6-12 exercises per routine

CrossFit WODs

Workout of the Day interval timing

• EMOM (Every Minute on the Minute)
• 10-20 minute workouts

Network Analysis

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Redirect Checker

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Perfect interval timer for workouts, HIIT, Tabata, circuit training, and exercise routines with customizable duration and repetitions.

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10 Minute Timer

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15 Minute Timer

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20 Minute Timer

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25 Minute Timer

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30 Minute Timer

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35 Minute Timer

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40 Minute Timer

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45 Minute Timer

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50 Minute Timer

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55 Minute Timer

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60 Minute Timer

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90 Minute Timer

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120 Minute Timer

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240 Minute Timer

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CST to MST Converter

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MST to CST Converter

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CST to PST Converter

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PST to CST Converter

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UTC to EST Converter

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PST to UTC Converter

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UTC to PST Converter

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GMT to EST Converter

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Paycheck Calculator

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Secure Password Generator

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Random Color Generator

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Random Color Picker

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Random Security Check

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Random Name Picker

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Random Decision Maker

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Random Team Generator

Generate random teams from a list of participants. Perfect for sports, group projects, or any activity requiring balanced team division.

Engineering

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Calculate output voltage, resistor values, power dissipation, and current for voltage divider circuits used in electronics and engineering.

Resistor Color Code Calculator

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Signal Frequency Calculator

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Fourier Series Visualizer

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Screensaver

A free backlight bleed tester to check dead pixels, backlight bleeding. Test monitor, laptop, mobile screen or other display issues.

Quickly detect dead pixels, screen flicker, or backlight bleed on any monitor with our advanced display testing tool.

Spot dead pixels, color uniformity issues, or backlight bleeding fast-ensure your screen quality with our pixel checker.

Instantly check for dead pixels, backlight bleed, or display defects to guarantee flawless screen performance.

Test your monitor for dead pixels, backlight bleeding, and color inconsistencies in seconds with our display diagnostic tool.

Identify dead pixels, uneven backlighting, or screen defects easily-optimize your monitor's display quality now.

Find and fix dead pixels, backlight bleeding, or display issues using our comprehensive screen testing solution.

Ensure perfect screen quality by detecting dead pixels, backlight bleed, and other monitor issues instantly.

Diagnose dead pixels, backlight bleeding, or display problems quickly-improve your monitor's performance and viewing experience.

Uncover dead pixels, backlight bleed, or screen defects fast with our user-friendly display testing tool.

Verify your screen for dead pixels, backlight bleeding, or color issues to maintain top display performance.

Easily detect dead pixels, backlight bleed, and other screen issues to ensure your display's optimal quality.

Quickly identify and troubleshoot dead pixels, backlight bleeding, and display defects for a flawless viewing experience.

Display the local time on your screensaver, automatically adjusting to your current time zone for accurate, real-time clock display.

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Elegant clock screensaver displaying the current time with customizable styles, perfect for adding a sleek look to your screen.

Utilities

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Flashlight Tester

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Morse Code Translator

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Spacebar Counter

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Password Strength Tester

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Printable

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February 2025 Calendar

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March 2025 Calendar

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April 2025 Calendar

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May 2025 Calendar

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June 2025 Calendar

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July 2025 Calendar

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August 2025 Calendar

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