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CalcAttendance vs CalcSpan

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

CalcAttendance compared with CalcSpan
DetailCalcAttendance logo CalcAttendanceCalcSpan logo CalcSpan
What it doesFree attendance calculator for students to track how many classes they can safely miss Date, deadline and time calculators with visible assumptions and sources
StageNot given Not given
FoundedNot given Not given
Based inNot given US
Pricing modelFree Free
PricingNot given Not given
Key features
  • Calculate how many remaining classes can be missed while staying at target
  • Determine how many consecutive sessions must be attended to recover if below threshold
  • Track attendance for multiple subjects separately
  • Browser-based with no sign-up or account required
  • All calculations performed locally without sending data to servers
  • 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
  • No account or sign-up needed – instant access with no data collection
  • All calculations happen in your browser – attendance data never leaves your device
  • Supports multiple institutional requirements with 75%, 80%, 85%, and 90% target options
  • Tracks multiple subjects simultaneously to prevent any single module from sliding below threshold
  • Built and maintained by a single developer focused on honest, accurate answers
  • 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 votes00
DR (Domain Rating by Ahrefs)Not checked yet no change since last checkNot checked yet no change since last check
Trust Flow (Majestic)10
Citation Flow (Majestic)190
Referring domains (Majestic)30

4 details filled in for both companies.

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