Slowly Stamp Collection Compare tool – Live !

Very useful tool for anyone seriously into stamp collecting

It's been 9 months since I posted the Full Release announcement topic on Reddit, here -– and we have added many, many new SLOWLY users who are getting into the fun; of enjoying the SLOWLY stamps and chasing, collecting them.

As of this morning, the total number of Slowly Stamps is up to 994 -– just 6 away from 1,000.

As a new Halloween 2021 stamp is likely to come this week, the 1,000 mark will be likely reached by November 1st.

With so many stamps, comparing Collections is near impossible

We used to do it manually, by eye — checking two browser tabs, one with ours and the other with a friend's collections.

This was doable when we had 100, 200, maybe 300 stamps, but got difficult as the number grew. One of my good penpal friends asked a friend to create a comparison tool, which he did. And soon posted, in the SLOWLYapp subreddit, his being version 0.2 - by Onumi.

And more development followed

I took an interest in the project and did some work, adding some changes and features, releasing them there. Versions 0.3, 0.3.3, and the most current which is version 0.3.5.

This version incorporates Responsive Design – and will work and display properly in a Desktop, laptop, Tablet or mobile phone device equally.

The Full Release post for v.0.3.5 is HERE, with more details, download links, explanations, etc.

Now Live on the Web !

Yes, we have it, and it has been appreciated by many collectors.

Live Version HERE, hosted on

Works on a Mobile device too

The tool running on a Samsung S9 Mobile phone

If running it on a mobile phone, please WAIT for it to process the collections, and display the results. Mobile devices have less processing power and this can be a bit intensive when collections are into the hundreds of stamps to compare.

What do you Need to use this Tool ?

Very simply, some stamp collections URLs. If you have a friend's URL (their webpage address), you can use that and compare to your own — and see what is missing from each of them, quickly.

And you can also use it with just ONE collection url — in which case, you leave the first collection input Blank, and enter your own in the second input box.

The tool uses a Reference Collection then, a large and very complete one – so you can quickly see how many stamps you are missing. And also which ones they are.

A comparison run, on my own local copy

A screenshot showing a comparison run - including the total number of stamps, and any missing ones in each - with the option to display each stamp's names.

This is a screenshot of my own local copy - which I have edited to insert my good friend's Collections URLs — so I can select any of them, including my own, as the 'Reference' one. As you can see, I was missing some – the very rare 'Hello Kitty' stamp sets.

Configuring your own 'reference' collections ?

There are 4 radio buttons, so you can select any of them for use as a collection comparison reference. And these could also be customized, to point to your favourite pen pal stamp collections.

Details are below, and it's VERY simple.

All you need is a Text editor (the simple Notepad in Windows even, that will do), to open the Compare_script.js file. And their collections URLs.

The four lines for these references are at the very TOP of the file (see screenshot below). A little edit, save and you will be able to use it customized for your own needs.

Optional – Editing the Reference Collections

Editing and adding your friend's collections is done here, right were the Yellow highlighted area is.

Just paste the URL (web page address) for each one of them, one in each line. Friend 1 is Collection 1, Friend 2 is Collection 2 and so on.

Since this is clearly marked and at the very top of the file, you can do the edits without worry or breaking the script below. Just keep the “ ” quote marks right where they are!

I saved my own collection into the 4th slot, and used the other 3 with friends that have large collections. Enjoy, also share with your pen pal friends! 😎👍🙂

Famous Last Words

Special Thank You to the folks behind this wonderful app — all the hard working people at Slowly Communications.

Letters we share, with pen pals all over the World, via the magic of the Slowly App. A modern day take in the traditional penpal experience.

Come and join us, if you are not yet using Slowly.

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