Latest Version:
3.0.0 Updated:
10 months ago
Ready to install?
Fast Calc is available to install from Firefox Add-ons Store and for download from this page.
1 ratings
0
Total downloads
Available versions
You can find the current and older versions of Fast Calc here. You can download the archived versions or inspect their source codes.
As a free user, you can download up to 3 latest versions.
Upgrade to download older versions
| Version | Download | Size | Download count | Timestamp |
|---|---|---|---|---|
| 3.0.0 | XPI · ZIP · Source code | 12.12MB | 0 | 2025-08-06 |
3.0.0 12.12MB
Install XPI file
An XPI file, short for "XPInstall," is a compressed file format used primarily by Mozilla applications, like Firefox and Thunderbird, to distribute and install add-ons or extensions. These files are similar in function to CRX files for Chrome but cater to the Mozilla ecosystem.
- Simply drag-and-drop the XPI into Firefox to install the add-on.
Install ZIP file
- Download the Fast Calc ZIP file.
- In Firefox browser, go to
about:addonsto open Add-ons Manager - Click on ⚙, Install Add-on From File

- Select the Fast Calc ZIP file from step 1. Fast Calc is now installed on your browser.
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