Doomsday Day of the Week Calculator | Find Any Date Instantly
Doomsday Day of the Week Calculator | Find Any Date Instantly is backordered and will ship as soon as it is back in stock.
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Product Details
Product Details
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Delivery and Shipping
Delivery and Shipping
All standard orders normally ship within 1 business day.
Custom orders normally ship within 2 business days.
Doomsday Day of the Week Calculator | Find Any Date Instantly
Description
Description
Quickly find the day of the week for any date between 1901 and 2099 with the Doomsday Day of the Week Calculator. Based on the mathematical method developed by John Conway in 1973, this handheld device simplifies the process, allowing anyone to determine the day of the week for any date in seconds.
What Is the Doomsday Rule?
In this context, "Doomsday" refers to a specific weekday in each year that anchors the calculation. By using this device, you can apply Conway’s rule without complex mental math.
How It Works:
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For Years 1901-1999:
- Locate the last two digits of the year on the large outer disk.
- Rotate the inner disk so the month is directly below the year.
- Find the day of the week next to the date on the inner disk.
- For leap years (marked in brackets), use alternate placements for January and February.
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For Years 2000-2099:
- Follow the same steps as above, then adjust back one day to align with the 21st-century calendar.
- Example: Dec 7, 1941 = Sunday → Dec 7, 2041 = Saturday.
Key Features:
- Fast & Easy Calculations: No need to memorize formulas or do mental math.
- Handcrafted Wooden Construction: Durable and elegantly designed.
- Instructions Engraved on Back: Never worry about losing them.
- Perfect for Math Enthusiasts: Great for educators, puzzle lovers, and history buffs.
- Made in the USA: Precision-crafted in our Hudson, Florida workshop.
Watch the Doomsday Calculator in Action:
Explore the power of mathematics with this unique handheld calculator. A must-have tool for history lovers, math geeks, and puzzle enthusiasts!
Personalize it!
Personalize it!
Click YES above the quantity selector to add a personalized laser engraving to your puzzle or game.
- Perfect for gifts
- Business marketing opportunity
Recommended age group
Recommended age group
Payment & Security
Payment methods
Your payment information is processed securely. We do not store credit card details nor have access to your credit card information.
Personalize It!
Did you know we can add a custom laser engraving to every puzzle and game? Well, we can. Add a personal touch to your gift with a name or message.
Frequently Asked Questions
Shipping
What countries do you ship to?
What countries do you ship to?
We ship all around the world. If you encounter an issue at checkout, please use the Chat Box to contact us. A real person will assist you.
How long will it take to receive my order?
How long will it take to receive my order?
Standard shipping normally takes 3-5 days. Next-day shipping is available on all domestic orders (for an additional charge). International shipping times vary depending on the product and destination (estimated at checkout).
Expedited shipping is available at checkout.
Returns and Refunds
How do I return a product?
How do I return a product?
Items must be returned within 30 days after receiving your order. Items must be returned in the same condition in which they were received, be unworn/unused, have any tags still attached, and include all the original packaging.
Custom/Personalized items can only be returned if we made a mistake on the customization/engraving.
How long will it take to receive my refund?
How long will it take to receive my refund?
Refunds are processed within 7 days from when we receive the item(s).
