Uses JSONBin.io — free storage, works in any browser, no account needed to sync once set up.
Not configured
One person does this once — takes 2 minutes:
1. Go to jsonbin.io and click Sign Up Free
2. After signing in, click Bins → Create New Bin
3. Paste in {} and save it
4. Copy your Bin ID (looks like 67a3f2...) and your Access Key
5. Paste both below, click Save credentials — then share the Bin ID with the other person
Stored only in this browser — never sent anywhere except JSONBin
Other person (read-only access): They only need the Bin ID — no account needed. Set the bin to Public in JSONBin settings so they can download without an access key. Or share your access key with them.
No credentials saved yet. Complete step 1 first.
How it works: Both people keep this HTML file. When one person makes changes, they click Upload. The other person clicks Download to get the latest. Last upload wins — no merge conflicts. ⚠ Only one person should upload at a time to avoid overwriting each other's changes.
Don't have the Bin ID yet? Share just the Bin ID with the second person — they enter it in step 1 (access key optional for public bins).
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