Send to Kindle by email

Quick answer

Email is the most flexible way to get documents onto a Kindle. Amazon's Send to Kindle email page lays out three steps: find your address, approve the email you'll send from, then attach the file. A subject line is optional.

What 125x is: 125x is a web app at 125x.app. You connect your YouTube subscriptions, and it gives you a feed of the latest videos from the channels you follow, each with a summary: a verdict, the 5 key takeaways, and the spoiler, plus Actionable and Lessons tabs with more tips. You read that and decide what's actually worth opening.

Open 125x

Setup

Go to Manage Your Content and Devices, then Preferences, then Personal Document Settings.
Copy the Send to Kindle address for the device or app you want.
Add the email you'll send from to the Approved Personal Document E-mail List.

Tips

Save the address as a contact named Kindle so it autocompletes.
Each device and app gets its own address. Pick the one you read on most.
Forward newsletters and long reads to it to read away from your inbox.

When nothing arrives

Check the sender is approved. This is the usual culprit.
Check the file type is on the supported list.
Look for a reply from Amazon with an error code, then try the web uploader.

Where 125x fits

On 125x, every video in your subscriptions feed comes with a summary: a verdict, 5 takeaways and the spoiler, plus an Actionable tab with steps and a Lessons tab with the bigger ideas.

FAQ: questions people ask

Where do I find my Send to Kindle email address?

Manage Your Content and Devices, then Preferences, then Personal Document Settings.

Do I need a subject line?

No. Amazon says a subject line isn't needed.

Why didn't my email reach my Kindle?

Most often the sending address isn't on your approved list.