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T TechnShield
Tool

Coin Flip Simulator

Flip a fair or biased coin with secure randomness, run large experiments, and export results. Live animation, stats, streaks, and CSV/JSON downloads.

For very large N, use backend CSV/JSON.

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Last flip
Heads: 0
Tails: 0
Heads %: 0%
Tails %: 0%
Longest H streak: 0
Longest T streak: 0
Results preview

              


              
              

                
 Secure RNG

                
 Reproducible (seeded)

                
 CSV export

                
 Live stats

              

            

          

        

      

    

  


  
  

    

      
How it works

      

        

          
1) Pick randomness

          
Secure (cryptographic), seeded (reproducible), or fast (browser PRNG).

        

        

          
2) Choose N and bias

          
Flip once with animation or run thousands with a custom Heads probability.

        

        

          
3) Export

          
Copy the sequence or download CSV/JSON. Use the backend for huge runs.

        

      

    

  


  
  

    

      

        
        

          

            
Randomness 101: Fair coins, PRNGs & seeds

            
What makes a coin flip "random"? When should you use cryptographic randomness vs a seeded PRNG? How big should N be to see ~50/50?

          


          

          

            
Fair vs biased

            
A fair coin has p = 0.5 for Heads each flip. A biased coin has p ≠ 0.5. Our tool lets you set p to simulate weighted coins.

          


          

            
Random number generators

            
    
              
  • Secure: cryptographically strong randomness from the browser (Web Crypto).
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  • Seeded: reproducible pseudo‑randomness; same seed → same sequence.
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  • Fast: the browser’s Math.random(), quick but not cryptographically strong.
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Law of large numbers

            
As N grows, the observed Heads % will tend toward the true probability p. Expect short‑term swings for small samples.

          


          

            
Streaks happen

            
Consecutive Heads or Tails streaks are common in random sequences. Long streaks don’t "correct themselves" — each flip is independent.

          


          

            
FAQ

            

              

                What’s exported to CSV?
                
Two columns: index (1‑based) and result (H/T). Use backend for very large runs.

              

              

                Are results truly random?
                
The Secure mode uses cryptographic randomness from your device. Seeded and Fast are pseudo‑random, good for demos and reproducibility.