LegitShow is the trusted source on every newly launched software product: what it does, who it’s for, how it actually holds up, and whether the AI engines are already reading it. Built to be what AI cites.

Web apps, SaaS, AI tools, MCP servers and developer tools. How we measure →

Legit.Show benchmarks every launched service it lists — measured deterministically from the public surface. See the methodology →

Cross-links · Directory · Reports · Insights · What AI reads · Methodology · About

Privacy · Terms · @Legit_Show on X · GitHub · operated by Madeflo Inc., a Delaware corporation. Benchmark engine powered by commit.show.

Ranked by measurement

Best fitness calculator

12 tested · top 12 shown

Ordered by a seven-frame production-readiness benchmark measured from each product's public surface — not popularity, pricing or feature count. Nobody pays to appear here and the order is never edited. How it is measured →
How this field scores
low 66median 81best 97
  1. 1
    Real Body Fat
    AI-based body fat estimation tool with a free Navy tape calculator.
    Perf 95
    Acce 100
    Sec 100
    Priv 100
    Rel 100
    Std 86
    Disc 100
    realbodyfat.com · measured 2026-09-26
    7/7 frames
  2. 2
    FitCalc HQ
    Free fitness and body calculators scored against real US military standards.
    Perf 99
    Acce 94
    Sec 45
    Priv 100
    Rel 100
    Std 100
    Disc 100
    fitcalchq.com · measured 2026-09-18
    7/7 frames
  3. 3
    BMI Calculator
    Free online calculator that computes Body Mass Index from weight and height.
    Perf 90
    Acce 91
    Sec 60
    Priv 100
    Rel 100
    Std 92
    Disc 100
    simplebmi.com · measured 2026-09-21
    7/7 frames
  4. 4
    FFMI Calculator
    Calculate your Fat-Free Mass Index to measure lean muscle relative to height.
    Perf 98
    Acce 92
    Sec 45
    Priv 75
    Rel 100
    Std 92
    Disc 100
    theffmicalculator.com · measured 2026-09-13
    7/7 frames
  5. 5
    RizzFit
    A collection of free fitness calculators covering nutrition, body composition, and training.
    Perf 78
    Acce 100
    Sec 45
    Priv 75
    Rel 100
    Std 92
    Disc 100
    rizzfit.orbitly.ca · measured 2026-09-24
    7/7 frames
  6. 6
    Calckoo
    Free health, fitness, and nutrition calculators built for Brunei and Southeast Asia.
    Perf 63
    Acce 96
    Sec 45
    Priv 75
    Rel 100
    Std 97
    Disc 100
    calckoo.com · measured 2026-09-24
    7/7 frames
  7. 7
    TDEE Calculator
    Free online calculator for total daily energy expenditure, BMR, and calorie targets.
    Perf 83
    Acce 94
    Sec 25
    Priv 75
    Rel 100
    Std 92
    Disc 100
    tdeecalculatorfree.net · measured 2026-08-19
    7/7 frames
  8. 8
    Cold Plunge Calc
    Free calculator that recommends safe cold plunge durations based on your goals and conditions.
    Sec 100
    Priv 25
    Rel 100
    Std 75
    Disc 100
    2 not assessed
    coldplungecalc.com · measured 2026-09-10
    5/7 frames
  9. 9
    RunKcal
    Free calculator that estimates kilocalories burned while running or on a treadmill.
    Perf 98
    Acce 79
    Sec 45
    Priv 45
    Rel 75
    Std 89
    Disc 87
    runkcal.com · measured 2026-09-10
    7/7 frames
  10. 10
    CalculCalories
    Free calorie calculator estimating TDEE, BMR, and macros in French.
    Sec 80
    Priv 0
    Rel 100
    Std 75
    Disc 100
    2 not assessed
    calculcalories.net · measured 2026-09-11
    5/7 frames
  11. 11
    FitKit
    Free fitness calculators, health tools, and training guides in one place.
    Perf 99
    Acce 88
    Sec 45
    Priv 0
    Rel 100
    Std 92
    Disc 72
    fitkit.top · measured 2026-09-09
    7/7 frames
  12. 12
    Body Mass Tools
    Free online calculators for BMI, Asian BMI, BMR, and ideal weight.
    Sec 25
    Priv 45
    Rel 100
    Std 75
    Disc 87
    2 not assessed
    bodymasstools.com · measured 2026-09-09
    5/7 frames
What this does not say
This ranks how production-ready each product's public surface is — not how well it does its job. For fitness calculator, that means it does not measure the quality of the work itself. Products whose sites block automated readers are left out rather than ranked last — we did not measure them, and bottom placement would claim something we never observed. Scores are floors: anything set at a CDN, a proxy or behind a login is invisible from the public surface.

All measured categories → · Browse the directory →