RN Number Calculator
Estimate the earliest production year of a textile product by its Registered Identification Number.
Enter the Registered Identification Number found on the garment’s tag. It must be a number greater than 13670.
What is an RN Number?
An RN, or Registered Identification Number, is a code issued by the U.S. Federal Trade Commission (FTC) to businesses in the United States that are involved in the manufacturing, importing, distribution, or sale of textile, wool, or fur products. This number allows a company to be identified without using its full business name on the product label. Many vintage clothing enthusiasts and resellers use the rn number calculator to get an approximate age of a garment.
The system began in 1952, but numbers were issued in a sequential, trackable manner starting from 1959. This makes it possible to estimate the year an RN was issued, providing a clue to the earliest possible date the associated garment could have been manufactured. You can find more information about dating vintage clothing on our blog.
RN Number Formula and Explanation
The calculation to estimate the issue year for an RN is based on historical data of how many numbers were issued each year. While not perfectly precise, it provides a very reliable ” manufactured no earlier than” date. The first RN issued in the trackable series in 1959 was 13670, and approximately 2,635 numbers were issued per year on average.
The formula used by the rn number calculator is:
Estimated Year = 1959 + ((Your RN Number – 13670) / 2635)
| Variable | Meaning | Unit | Typical Range |
|---|---|---|---|
| Your RN Number | The Registered Identification Number from the tag. | Unitless Integer | 13671 – ~150000+ |
| 13670 | The first RN number issued in the 1959 series. | Unitless Integer | Constant |
| 2635 | The average number of RNs issued per year. | Numbers/Year | Constant |
| 1959 | The base year for the calculation. | Year | Constant |
Practical Examples
Using the calculator can help you quickly assess vintage finds. Here are a couple of realistic examples:
Example 1: A 1970s Era RN
- Input (RN Number): 55749
- Calculation: (55749 – 13670) / 2635 = 16.0 years
- Result: 1959 + 16 = 1975
- Interpretation: The company associated with this RN was registered around 1975. The garment could not have been made before this year.
Example 2: A 1990s Era RN
- Input (RN Number): 98765
- Calculation: (98765 – 13670) / 2635 = 32.3 years
- Result: 1959 + 32 = 1991
- Interpretation: This RN was likely issued in 1991. For tips on how to preserve such items, see our guide on textile care.
How to Use This RN Number Calculator
Using this tool is straightforward:
- Locate the RN Number: Find the care or brand tag on your garment. The RN number is typically printed there.
- Enter the Number: Type the number into the input field above. Ensure you are only entering the digits.
- Interpret the Result: The calculator will instantly show the estimated year the RN was issued. This is the earliest possible date your item was produced. The actual manufacturing date could be that year or any year after.
Key Factors That Affect RN Number Dating
- Average Rate Fluctuation: The formula uses an average of 2,635 new numbers per year. In reality, some years had more and some had fewer, so the result is an estimate.
- Company Lifespan: A company could have been issued an RN in 1970 but the garment you hold was manufactured in 1995. The calculator only gives the starting point.
- Post-1998 Database: The FTC maintains a searchable online database for RNs, but it’s most accurate for those issued or updated after 1998. This calculator is most useful for pre-1998 numbers.
- WPL Numbers: An older system called WPL (Wool Products Labeling) existed from 1941-1959. These numbers are different and cannot be used in this rn number calculator.
- Company Transfers: An RN can be transferred if a company is sold. This can sometimes complicate the history, though the original issue date remains the same.
- CA Numbers: Canadian garments use a “CA Number,” which is a separate system not compatible with this calculator. Check out our guide to international labels.
Frequently Asked Questions (FAQ)
- Is the RN number the same as the patent number?
- No, they are completely different. An RN is for identifying a textile business, while a patent protects an invention.
- Why does my garment not have an RN number?
- RN numbers are not mandatory. Companies can choose to use their full business name on the label instead.
- Can I find the company name from the RN number?
- Yes, you can search the FTC’s official RN Database. This is most reliable for numbers issued or updated after 1998.
- What if the calculator gives a future date?
- This is highly unlikely but could indicate a data entry error or an extremely new RN number not yet accounted for in historical averages.
- Does the RN number tell me where the garment was made?
- No, it only identifies the U.S. business responsible for it. The country of origin is a separate requirement on the label.
- What is a WPL number?
- WPL (Wool Products Labeling) numbers were issued before RNs, from 1941 to 1959. They are part of a different numbering system.
- Is this calculator 100% accurate?
- No, it provides an estimate. It is based on the average number of RNs issued per year and is a trusted method among vintage sellers for establishing a “no earlier than” date.
- Can I use this calculator for a CA number?
- No. CA numbers are for Canadian businesses and follow a different system. You can learn more in our comparison of label types.
Related Tools and Internal Resources
If you found our rn number calculator useful, you might be interested in these other resources:
- Vintage Clothing Style Guide: Learn to identify different fashion eras.
- Textile Preservation Tips: Keep your vintage finds in pristine condition.
- Understanding Clothing Labels: A deep dive into what all the symbols and numbers mean.