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 localStorage only.
• 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).

Support the project

If the calculators or guides are useful, you can support the project with a voluntary donation. It does not unlock the 8-week plan: the calculators stay free and do not require an account. Lemon Squeezy processes the payment.

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.