BabyPercent is a free online tool — Free baby growth percentile calculator (0-24 months). Weight, height, head circumference. WHO & CDC data.
BabyPercent was built by an independent developer using AI-assisted coding tools. The entire site was built with Claude Code and Next.js, deployed on Cloudflare Pages. No venture funding, no big team. Just one person with AI as a force multiplier, shipping useful tools to the world.
BabyPercent is supported by advertising (Google AdSense). You get full access to all tools without paying anything, and we earn a small amount when ads are viewed. No paywalls, no premium tiers. If ads are annoying, use an ad blocker — the tools still work perfectly.
Your files never leave your device. All processing happens locally in your browser. Read more on our Privacy Policy page.
Built with Next.js 16 (static export), deployed on Cloudflare Pages for global edge performance. Pure JavaScript and WebAssembly engines — zero server-side processing, zero uploads.
Percentile reference data is sourced from the WHO Child Growth Standards (0–24 months) and the CDC Growth Charts. This tool computes percentiles mathematically from these public reference tables. It is an educational planning tool, not a medical device. It does not diagnose, screen for health conditions, or replace a pediatrician's assessment. A single percentile reading does not indicate a health problem — growth trajectories over time matter more than any single data point. If you are concerned about your baby's growth, feeding, or development, speak with your pediatrician.