Free Fitness Calculator Widgets

7 powerful, embeddable fitness calculators. Free to use on any website. Increase engagement, reduce bounce rate, and provide real value to your audience.

Gym ROI Calculator

Most Popular

Perfect for gym consultants & business resources

Help your visitors evaluate gym investment potential with this professional ROI calculator. Calculates total investment, monthly profit, payback period, and annual ROI.

  • Initial investment breakdown (equipment, buildout, working capital)
  • Monthly revenue calculator (members × fee + other revenue)
  • Monthly expenses (rent, payroll, other)
  • 8 key metrics: total investment, monthly profit, payback, annual ROI
  • Responsive design, works on all devices
<iframe src="https://www.zeallsport.com/roi-widget.html" width="350" height="650" frameborder="0" title="Gym ROI Calculator | Powered by ZEALLSPORT" style="border:none;max-width:100%;"></iframe>

BMI Calculator

High Engagement

Perfect for health & fitness blogs

A clean, intuitive BMI calculator with metric and imperial unit toggle. Includes visual BMI scale marker and category classification (underweight, normal, overweight, obese).

  • Metric (kg/cm) and Imperial (lb/in) unit toggle
  • Visual BMI scale with position marker
  • Color-coded category badges
  • Instant calculation, no page reload
  • Lightweight, fast loading
<iframe src="https://www.zeallsport.com/widgets/bmi-calculator.html" width="320" height="500" frameborder="0" title="BMI Calculator | Powered by ZEALLSPORT" style="border:none;max-width:100%;"></iframe>

Calorie & Macro Calculator

Feature Rich

Perfect for nutrition & training websites

A comprehensive calorie calculator using the Mifflin-St Jeor equation. Calculates BMR, TDEE, target calories based on goals, and provides a full macronutrient breakdown (protein, carbs, fat).

  • Mifflin-St Jeor BMR equation (most accurate)
  • 5 activity levels (sedentary to extra active)
  • 5 goal settings (lose weight to gain weight)
  • Macronutrient split with visual bar (40/40/20)
  • Daily water intake recommendation
<iframe src="https://www.zeallsport.com/widgets/calorie-calculator.html" width="350" height="700" frameborder="0" title="Calorie & Macro Calculator | Powered by ZEALLSPORT" style="border:none;max-width:100%;"></iframe>

1RM One Rep Max Calculator

Strength Training

Perfect for strength training & powerlifting sites

A professional 1RM calculator with 6 different estimation formulas (Epley, Brzycki, Lander, Lombardi, Mayhew, Wathan). Includes a full percentage-based training weight chart for programming.

  • 6 estimation formulas (Epley, Brzycki, Lander, Lombardi, Mayhew, Wathan)
  • kg and lb unit toggle
  • 6 exercise presets (bench, squat, deadlift, OHP, row, other)
  • Percentage training chart (60%-100% of 1RM)
  • Approximate rep ranges for each percentage
<iframe src="https://www.zeallsport.com/widgets/1rm-calculator.html" width="350" height="650" frameborder="0" title="1RM One Rep Max Calculator | Powered by ZEALLSPORT" style="border:none;max-width:100%;"></iframe>

Bench Press Calculator

Strength Training

Perfect for bench press & chest training content

A dedicated bench press calculator with 1RM estimation, strength level classification based on bodyweight ratio, and a complete training percentage table for programming bench press workouts.

  • Epley & Brzycki 1RM formulas (auto-selects based on reps)
  • kg and lb unit toggle
  • 5 strength levels (Beginner to Elite) based on BW ratio
  • 9 training percentages (50%-95% of 1RM) with rep schemes
  • Training focus labels (warm-up, hypertrophy, strength, power, peaking)
<iframe src="https://www.zeallsport.com/widgets/bench-press-calculator.html" width="350" height="700" frameborder="0" title="Bench Press Calculator | Powered by ZEALLSPORT" style="border:none;max-width:100%;"></iframe>

Squat Calculator

Strength Training

Perfect for squat & leg day training content

A dedicated back squat calculator with 1RM estimation, squat-specific strength standards (higher thresholds than bench), and a complete training percentage table for programming squat workouts with mobility and technique focus.

  • Epley & Brzycki 1RM formulas (auto-selects based on reps)
  • kg and lb unit toggle
  • Squat-specific strength levels (Beginner to Elite, higher BW ratios)
  • 9 training percentages (50%-95% of 1RM) with squat-specific rep schemes
  • Training focus labels (mobility, technique, hypertrophy, strength, power, peaking)
<iframe src="https://www.zeallsport.com/widgets/squat-calculator.html" width="350" height="700" frameborder="0" title="Squat Calculator | Powered by ZEALLSPORT" style="border:none;max-width:100%;"></iframe>

TDEE Calculator

Nutrition & Goals

Perfect for nutrition, fat loss & muscle gain content

A comprehensive TDEE (Total Daily Energy Expenditure) calculator using the Mifflin-St Jeor BMR equation. Calculates BMR, TDEE based on 5 activity levels, and provides 3 calorie goal cards for fat loss, maintenance, and muscle gain.

  • Mifflin-St Jeor BMR equation (most accurate available)
  • Metric (kg/cm) and Imperial (lb/in) unit toggle
  • Male/Female gender selection
  • 5 activity levels (sedentary to extra active)
  • 3 goal cards: Fat Loss (-500 cal), Maintain (TDEE), Muscle Gain (+300 cal)
<iframe src="https://www.zeallsport.com/widgets/tdee-calculator.html" width="350" height="650" frameborder="0" title="TDEE Calculator | Powered by ZEALLSPORT" style="border:none;max-width:100%;"></iframe>

Why Embed Our Widgets?

Increase Engagement

Interactive tools keep visitors on your site 2-3x longer, reducing bounce rate and increasing page views per session.

Build Authority

Offering professional calculators positions your site as a trusted resource in the fitness industry.

100% Free & Fast

No fees, no subscriptions, no sign-ups. Just copy and paste. Lightweight code that won't slow your site.

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