About PesaFit
PesaFit is an independent fitness & nutrition project built by Jesús Narváez Tamés, a software engineer based in Madrid (Spain).
Why this exists
In 2022 I went from 106 kg to 82 kg over about eight months. The biggest barrier wasn't willpower — it was the lack of free, no-signup tools that would tell me my real maintenance calories, how to split macros, how much protein I actually needed, or how to progress a barbell program with sane numbers. PesaFit is the site I wish I had then.
Methodology
- Evidence-based. Every guide cites the original source (ISSN, EFSA, OMS, peer-reviewed meta-analyses). Calculators use widely validated formulas: Mifflin-St Jeor for BMR (1990), Epley for 1RM, OMS guidelines for hydration, ISSN ranges for protein, Karvonen for heart-rate zones.
- Privacy-first. Calculators run entirely in your browser. We never see your weight, height or any input. Your optional profile lives in
localStorageonly. - No medical advice. Everything here is educational. Decisions about your training, diet or health must be made in consultation with a qualified professional.
- Transparent monetization. We display Google AdSense ads and recommend some products via Amazon affiliate links (your price doesn't change; we receive a small commission if you buy). We never recommend a product we wouldn't buy ourselves.
What you'll find
- 13 calculators grouped in 4 categories (nutrition, strength training, cardio, competition).
- 41 long-form guides in 9 topical clusters — currently being translated to English.
- A meal-plan generator and a strength-training routine generator (Spanish-only today).
Contact
Email jesus.narvaez.tames@hotmail.com for editorial feedback, factual corrections or partnership inquiries. For the full personal story (in Spanish), see the Spanish version of this page.