How to filter out old email from inbox

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Every few years I take a pass at reducing the chaos in my personal inboxes. There are simply too many emails to deal with, and that generally leads to me increasingly failing to follow up on important email.

Up to this point, my strategy has largely been filtering out emails that I never want to read. But there’s another category of email which is stuff I often want to read when it’s fresh, but never want to read after it’s fresh. For example, calendar reminders, some mailing lists, some news letters, etc.

I decided to figure out how I could setup a system where I could mark a number of things as “filter three days after receipt”. This is a nice compromise, because I do want to see those things, but I don’t want to have to remember to archive them after the fact.

You can write a search query for this in GMail:

from:(calendar-notification@google.com) older_than:3d

However, if you try to create a GMail filter using that, it turns the older_than:3d into a fixed point in time rather than doing what you want.

The image shows a Gmail search filter setup, looking for emails from “calendar-notification@google.com” that are older than three days and have a size greater than a specified amount, dated within one day of May 3, 2025. Options to filter by attachments and exclude chats are available, with “Create filter” and “Search” buttons at the bottom.

It seems that this is unsolvable within GMail itself. However, some quick searching suggested it was possible to create a Google App Script to solve this, and asked Claude to write the script for me.

Following those instructions, I went to script.google.com, which I have not gone to in many years. I edited the generated script from Claude to use the tag “TempMsg”, to archive messages (as originally it had those commented out), and to limit itself to the first fifty items matching that tag. You can find the full code in this gist.

This image provides instructions on setting up a Google Apps Script to filter Gmail messages with a tag older than three days. It includes steps for opening Gmail settings and creating a new script project.

I attempted to run this as is, and got an error message that I needed to grant permissions. That requires three clicks within the Google Scripts UI.

The image shows a Google Apps Script interface where a user is adding the Gmail API service to a project. Red arrows highlight the action of selecting the Gmail API from a list of services and the “Add” button.

This also requires approving the somewhat scary message that I trust myself.

The image displays a warning that Google hasn’t verified a specific app, advising users not to use it until the developer verifies it with Google due to its request for sensitive account information. Users have the option to return to safety or proceed with caution if they trust the developer.

From there I tried to run this script, and it failed because the TempMsg tag doesn’t exist in my inbox.

The image shows a script written in JavaScript for Google Apps Script, designed to filter Gmail messages older than three days with a specific label. The execution log indicates that the label “TempMsg” was not found during the script’s execution.

So I went ahead and created that tag, and setup some filters to assign that tag to certain email senders.

This image shows the Gmail filter creation settings page, where emails from “calendar-notification@google.com” are set to be labeled as “TempMsg.” Options for other actions like skipping the inbox, marking as read, or forwarding are available but not selected.

After that, I was able to run the script and it worked properly. Note that I convinced myself that it was failing for a bit, because it doesn’t remove messages from the past three days. That is exactly how it’s supposed to work, but I would run it and then see messages with the tag there and think it was failing. Woops.

After convincing myself it was working, I added a periodic trigger to run this.

This image shows a Google Cloud Platform interface for adding a time-driven trigger to run the function “filterOldGmailMessages” daily between midnight and 1am, with immediate failure notifications.

I now have this running on a daily basis, and it’s given me a nice new tool for managing my email a bit better. After verifying it, I also used the tag manager to “hide” this tag in the inbox, so I don’t have to see the TempMsg tag everywhere. If I ever need to debug things, I can always make it visible again.