About Postcrossing Lab
Postcrossing Lab is a calm, privacy-first way to exchange real postcards with members around the world. Send a card to someone you have never met, and receive one back from somewhere unexpected.
How it works
Request an address
Get a random member's address and a unique Postcard ID.
Send a postcard
Write the Postcard ID on a card and mail it.
Receive a postcard
Another member sends a card your way in return.
Register the ID
Enter the Postcard ID you receive to record the exchange.
Repeat
Keep the loop going and grow your collection.
How to get started
Setting up takes only a few minutes. Follow these steps to send your first postcard.
Create your account
Sign up with your email and a one-time code. No password to remember.
Complete your profile
Add your mailing address and a few words about the cards you enjoy. Your address stays private and is only shared with the member sending to you.
Request an address
Ask for a random member's address and a unique Postcard ID to write on your card.
Send and register
Mail your postcard, then register the IDs of the cards you receive to keep the loop going.
Frequently asked questions
Answers to the questions members ask most often before their first exchange.
Is my address kept private?
Yes. Your mailing address is only shared with the member who is sending a postcard to you, and never appears on your public profile. We never expose your email or full address publicly.
What is a Postcard ID?
A Postcard ID is a unique code you write on each card. When the recipient registers that ID, the exchange is recorded and the next postcard can travel.
How are recipients matched?
When you request an address, the system picks a random member who is ready to receive a card, so every postcard reaches someone new.
How long does a postcard take to arrive?
Delivery times vary by destination, usually from a few days to several weeks. Patience is part of the fun of postcrossing.
What happens if a postcard never arrives?
Some cards are lost in the post. It is normal and expected, so it does not count against you. Keep sending and the loop continues.
Ready to send your first postcard?
Create a session with a one-time email code, complete your profile, and join the global exchange today.