Some statistics about LoTW



Number of known user calls

I started this project in March 2005.

A major effort to build the list was done in July-August 2005, which brought the list to the 9000 calls level.

After that time, with the help of over 700 contributors, the list continued to grow quite regularly, with an average of about 10,000 new calls yearly in the recent time.

1. Sudden increases of the curve are the result of sometimes using some very effective, but time consuming, sources of new calls. They don't mean that so many users joined LoTW just at those specific dates.
2. The big jump in 2017 results from the release of the full users list by the ARRL, which provided almost 4000 new calls.

Last upload date to LoTW

(108,387 users on 2017-07-31)




38,725 users (35.7 %) uploaded since early 2017 (7 months ago).

53,654 users (49.5 %) uploaded since early 2016 (19 months ago).


Cumulative table


Number of users who uploaded since the beginning of each year till the date the stats were generated (see above).

For example: 63,820 users (58.9 %) uploaded between 2015-01-01 and the date the graph was created.


My LoTW QSL rate over the time (old)

Those statistics were established in January 2008 based on almost 15,000 QSO's I entered on the system for the years 1980-2004, mostly HF CW and phone.

In 2005, I started working LoTW participants selectively, so my QSL rate became much higher but has no more statistical meaning.

This graphic shows quite a good QSL rate since about 1997 (around 15 %), an "acceptable" one till 1989 (mostly 4 to 7 %), and a very low one (just above 1 %) for most of the 80's.