Sharing & Collaboration
Share, embed, and collaborate on calculations with permanent URLs.
Click Share to make a calc public. You’ll get a short link and can copy an edit link for collaborators.
URL Formats
View Links
Anyone with the link can use your calc (play with numbers), but the original is unchanged.
| Format | Example | Use |
|---|---|---|
/<shortId> | instacalc.com/j2k8npm | Short link |
/<shortId>/<slug> | instacalc.com/j2k8npm/mortgage-calc | Canonical link (slug is cosmetic) |
/<integer> | instacalc.com/12345 | Legacy link (still works forever) |
Edit Links
Append #token to any view link to grant edit access. The token is a secret — only share it with people you trust to edit.
| Format | Example |
|---|---|
/<shortId>#<token> | instacalc.com/j2k8npm#x9Km4p_B |
Editors see the same calc and their changes sync in real time. The #token is never sent to the server — it stays in the browser, so it won’t leak in server logs or social previews.
Scenario Overrides
Add ?key=value to a view link to pre-fill variables. Great for sharing specific scenarios.
| Format | Example |
|---|---|
/<shortId>?rate=7.5&years=15 | instacalc.com/j2k8npm?rate=7.5&years=15 |
Overrides are read-only — the viewer sees your calc with different numbers, but nothing is saved.
Embeds
Append /embed to any calc URL for an iframe-friendly version.
| Format | Example |
|---|---|
/<shortId>/embed | instacalc.com/j2k8npm/embed |
Embed code:
<iframe title="Embedded calculator" src="https://instacalc.com/j2k8npm/embed" width="600" height="400" frameborder="0"></iframe>The legacy prefix form /embed/<calcId> (e.g., instacalc.com/embed/12345) also works and will continue to work for existing embeds.
Formula URLs
Encode a calc directly in the URL — no account or saving needed.
| Format | Example |
|---|---|
/<expression> | instacalc.com/x=100;tax=x*8%;total=x+tax |
Semicolons separate rows. Underscores become spaces. These are stateless — the calc lives entirely in the URL.
Live Rooms
Hash-based rooms for ephemeral collaboration.
| Format | Example |
|---|---|
/#<room-name> | instacalc.com/#team-budget |
Anyone with the same link edits the same calc in real time. No account required.
Demo
Shared calc: instacalc.com/42214
Embed:
Three Signals
The URL tells you everything:
#= edit key (or live room)?= scenario override- no fragment = read-only view