Clarion Date Converter
Convert Clarion date values (days since December 28, 1800) to and from regular dates - useful for reading legacy Clarion application databases.
Recommended Settings
Pro Tips
- •Edit either the Clarion date value or the date/time field - the other one updates automatically
- •Use the Copy buttons to grab any value in the format you need, including Unix seconds, milliseconds, or ISO 8601
- •Click Use Current Time to instantly see the current moment represented in this format
- •This runs entirely in your browser - nothing you enter is sent to a server
Most Popular
Most users paste in a raw value from a database or log file to see what date and time it actually represents
When to Use This Tool
Convert a raw Clarion date value into a readable date and time.
Work backward from a known date to the equivalent Clarion date value.
Quickly verify what a specific timestamp value actually represents.
Figure out why a timestamp value looks wrong by converting it to a human-readable date.
How It Works
Take the Clarion date value you enter, which represents whole days elapsed since December 28, 1800, the epoch used by the Clarion programming language's date data type
Convert it to a standard Unix millisecond timestamp using the correct epoch offset and unit scale
Display the result in several common formats, and support converting in the opposite direction too
100% Private
Files never leave your device. All processing happens locally in your browser.
Lightning Fast
Powered by Client-side epoch arithmetic for optimal performance on modern browsers.
Open Source
Built with verified, open-source libraries. Fully transparent.
Frequently Asked Questions
What epoch does this format use?
Whole days elapsed since December 28, 1800, the epoch used by the Clarion programming language's date data type.
Why would I need to convert this format?
Clarion is a programming language and database system used in many legacy business applications, particularly from the 1990s and 2000s, and its native date type counts whole days since December 28, 1800.
Is my data sent to a server?
No. All conversion happens entirely in your browser using JavaScript.
Does this account for timezones?
The underlying timestamp is timezone-independent (a single point in time), and the 'Date & Time' field shows it in your browser's local timezone alongside UTC for reference.
What if I enter an invalid value?
The tool will show a warning that the value doesn't look valid rather than silently displaying an incorrect date.