The Bitcoin Heater contest is closed!

How We Picked the Winners

To keep the contest fair, transparent, and nerdy in all the right ways, we used a method based on Hamming distance — a way of measuring how similar two digital fingerprints (called hashes) are.

Each participant submitted a SHA256 hash, created from anything they liked: a favorite recipe, a secret phrase, the name of their cat — you name it.

Meanwhile, we had already pickedthree target hashes before the contest began. To ensure a fair competition, we’d already published the SHA256 hash of the concatenated winning target hashes below:

cdbe74ac4218ed5a43b5417def92bd0b7a5d422e8433f97e7955ac7fe1d34630

The three target hashes that lead to this outcome are available now:

1112204739fc46a8a786efce041c745a

3cb622969ba65505613c750dbd218ef2

527ff0c9614a30000dcc01831bdd99f5

After the deadline passed, we compared all submitted hashes to each target hash.

For each one, we calculated how many bits were different between the two hashes — this is called the Hamming distance. The smaller the number, the closer the match.

Here’s how we made the final picks:

• We identified the submitted hash that was closest to each of the three target hashes.
• For each target, we found the closest hash.
• If a hash had already been used as a winner, we skipped it and picked the next closest unique one.

This Means:

• Three different people are walking away with brand-new Bitcoin heaters.
• Everyone had the same chance, no matter what they hashed.
• And best of all: the process can be verified by anyone with the original hashes.

Thanks to everyone who participated — and keep your eyes peeled for the next challenge hidden in Transit!

And now, the winners are:

Surprisingly, out of over 1,000 readers, there are just eight (!) valid form inputs (some people just wrote 'SHA256' etc and as a result of that, could not be included in the draw), here they come:

9a9a49da71b6f446ef4302868318a1ac57e935be6636d538adfbab42e4061bed

005d93f59200e68fffa5b8a4a0d8ed915ad61b07b846a71266e76672c3a816f2

69f9f80e1f73e836c69eb1e5afd858b9a7df2df20a6ce0c0698230aea7ca6338

bb4c0e1c6e7453a91a197a3476caff5491702834e88bf66043b380b4102330f0

c856555efa65dd16a2ecff3c6efdc9e64bc54ad05fd0b854e7d4b4c43cdd6507

ce40b54d67b5cf7c406dad8a61570194ec3dff4a9dfe75a83840b9cbb9e24594

6d840d1ff67c25aa5bdf02bcc56558cec0164482f7fa275a0744d60a7adb1a96

e1b39559ce29c235ab8387b82d4e7137641875b5d09e176925ddab57f5d98125

Winners

1. Closest to Target Hash 1
   9a9a49da71b6f446ef4302868318a1ac57e935be6636d538adfbab42e4061bed
   → Hamming Distance: 60
2. Closest to Target Hash 2
   c856555efa65dd16a2ecff3c6efdc9e64bc54ad05fd0b854e7d4b4c43cdd6507
   → Hamming Distance: 58
3. Closest to Target Hash 3 (next closest that’s not already a winner)
   69f9f80e1f73e836c69eb1e5afd858b9a7df2df20a6ce0c0698230aea7ca6338
   → Hamming Distance: 59

Each of these three entries came closest to one of the target hashes, and all are from unique participants.

Check your mail to see if you're the lucky one, and reply with your address details, so I can provide them to 21energy.com in Austria.

Well done, and thank you!

Harper.