Select a validity, copy one password, encrypt your file with copied password, provide pwd4.ch and password index to your recipient (ideally by phone), you made a strong password exchange without track!
For security reasons, expired passwords are not saved!

Daily
Calculation in progress
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Weekly
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Monthly
Calculation in progress
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Random
Allways changing
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Weekly (Shifted)
Calculation in progress
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Monthly (Shifted)
Calculation in progress
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Total possibilities : 87^24 = 3.535 x 10^46 = 35'355'913'511'525'016'643'527'540'154'987'349'596'888'122'561