Pregnancy Metrics vs CalcSpan

A side-by-side comparison built from both listings. Blank cells mean the company has not given that detail; we never guess.

Pregnancy Metrics compared with CalcSpan
Detail	Pregnancy Metrics	CalcSpan
What it does	Free pregnancy and preconception calculators	Date, deadline and time calculators with visible assumptions and sources
Stage	Not given	Not given
Founded	Not given	Not given
Based in	Not given	US
Pricing model	Free	Free
Pricing	Not given	Not given
Key features	Browser-based calculations without account needed Plain-language methodology guides Local weight-gain tracker storage	184 calculators across 53 categories Shows counting rules and assumptions with each result Local-first processing with no data sent to servers Holiday and weekend calendar selection Business day counting Date arithmetic (add or subtract days, weeks, months, years) Sleep cycle planner with NIH-based 80-100 minute cycles Time zone conversion with DST handling Save results as images or add to calendar Schengen visa 90/180 day rolling window auditing
What makes it different	Independent development with no external clinician certification claimed Calculations processed in browser only, not stored in project-controlled database Methods and claims tied to published sources	Shows the source and counting rule beside every answer No sign-up or account required to use any calculator All inputs stay in your browser for privacy Comprehensive coverage across 53 life and work categories Higher-risk calculators include prompts to verify with professionals
Community votes	0	0
DR (Domain Rating by Ahrefs)	Not checked yet no change since last check	Not checked yet no change since last check
Trust Flow (Majestic)	0	0
Citation Flow (Majestic)	12	0
Referring domains (Majestic)	1	0

4 details filled in for both companies.

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