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ReactionTests vs FPSDEN

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

ReactionTests compared with FPSDEN
DetailReactionTests logo ReactionTestsFPSDEN logo FPSDEN
What it doesTest your visual reaction time for free Free browser tools for random picks, printable practice, wheels and data conversion
StageNot given Startup
FoundedNot given 2026
Based inNot given Not given
Pricing modelFree Free
PricingNot given Not given
Key features
  • Five-round visual reaction test with millisecond timing
  • Seven-round sound reaction time test
  • Local result history with up to 300 sessions stored
  • Consistency measurement showing standard deviation of scores
  • Download score card as image
  • Sound calibration for personal offset adjustment
  • Reference data from published research studies
  • Random Number Generator with customizable range and quantity
  • Random Letter Generator for A–Z selection
  • Random State Generator for 50 U.S. states
  • Random Number Wheel with editable options and weights
  • Worksheet Generator for fraction practice and handwriting
  • Country Wheel with 193 UN member states
  • Truth or Dare Wheel with family-friendly prompts
  • JSON to CSV Converter with delimiter and BOM options
  • UUID Generator for v4 or v7 with multiple options
  • Cursive Generator for Unicode text conversion
What makes it different
  • No account or login required to use the test
  • Results stored locally in browser for privacy
  • Compare full sessions to understand consistency, not just fastest round
  • Research-backed reference data from laboratory studies
  • Everything runs locally in your browser without server uploads
  • No account or sign-up required
  • Continuous tool corrections and FAQ pages with examples
  • Uses browser cryptographic random source with rejection sampling
Free planNot given Not given
Open sourceNot given Not given
PlatformsNot given Not given
Public APINot given Not given
Community votes00
DR (Domain Rating by Ahrefs)3 no change since last checkNot checked yet no change since last check
Trust Flow (Majestic)00
Citation Flow (Majestic)110
Referring domains (Majestic)10

4 details filled in for both companies.

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