What are date codes and how do you find them?
What are Date Codes?
Date codes are the week and year of manufacture of the products. Our customers care about them because they represent the quality of the goods and sometimes correspond to changes in the firmware (or programming) on the devices.
The format of the date code is mostly in the form of a YYWW format. The first two digits (YY) represent the last two digits of the year, while the last two digits (WW) stand for the week of the year.
Where can you find Date Codes on the physical product?
Date codes are typically found in one of two places:
On the original invoice
On the label on the reel
Date code formats
✅ 21+ (means the date code is 2021 or later)
✅ 19+ (means the date code is 2019 or later)
✅ 0327 (means the product was made in the 27th week of 2003)
✅ 1819 (means the product was made in the 19th week of 2018)
❌ 02/08/2008 → How to fix: Look up the week and date here: timeanddate.com/date/weeknumber.html. This should be "0806"
❌ 21+ and 22+ → How to fix: Use the minimum of the two, e.g., "21+"
❌ 0325, 0337, 92211, 62221 → How to fix: Use the minimum of these, e.g., "03+"
❌ 62221 → How to fix: Most likely Excel recreated this date into its internal date format. Look at the original file, get the date, and recalculate the week number.
❌ 2021+ → How to fix: Change to "21+"
Buying parts from Mobius
If a date code is provided on a listing, then you accept that date code for your order.
If no date code is provided on the listing, Mobius assumes the parts are within the last 3 years of manufacture. If the actual date code on the parts you receive falls outside that window, you're entitled to a discount off the order price or the option to cancel the order, depending on how far outside the window it falls.
DC Age | Final Price |
3–5 years old | 70% of the original price |
5–7 years old | 50% of the original price |
Over 7 years old | You can cancel or submit a revised offer |
A part's date code can affect whether it's eligible for import into your country. Some countries restrict the import of components with date codes older than 10 years including China. We'll flag any parts that may not clear customs due to date code age before the order is finalized.
How to find the date code of a listing
The date code, if provided by the seller, appears in the listing details alongside the MPN, manufacturer, and quantity. To check it:
Open the listing you're interested in.
Look for the Date Code field in the part details panel.
If no date code is shown, it means the seller hasn't provided one — in that case, the 3-year assumption above applies, and any discrepancy will be handled per our pricing policy.
If you have a strict date code requirement we will check with the seller on your behalf. Submit this request by emailing [email protected] before placing your order.
Selling parts to Mobius
A part's date code (DC), or the week and year it was manufactured, affects its resale value. We know it can be a hassle to identify the DC on every part before shipping. If you'd rather send the parts and have us gather that info at our facility, we're happy to help and adjust pricing based on what we find.
Unless it is provided, Mobius purchase orders assume a DC within the last 3 years. If the actual DC falls outside that window, pricing will adjust as follows:
DC Age | Final Price |
3–5 years old | 70% of the PO value |
5–7 years old | 50% of the PO value |
Over 7 years old | We can't guarantee the order — buyer may cancel or submit a revised offer |
We'll confirm any adjustments before processing the order.
How to add a date code for a listing
You can add a date code to a listing in two ways:
When creating a listing manually:
Look for the Date Code field on the listing creation/edit form and enter it using one of the accepted formats above (e.g., "21+" or "0327").
When uploading listings in bulk via CSV:
Include the Date Code column in your upload file. This is an optional but recommended column. It locks in the date code on the listing and helps avoid pricing adjustments down the line. See our Uploading Listings via CSV article for the full column list and formatting rules.
If you're unsure of the exact date code, it's better to leave it blank than guess. An incorrect date code can cause more friction at order time than no date code at all.