How Gmail's 15 GB storage limit works
A free Google Account comes with 15 GB of storage, and that 15 GB is not Gmail's alone. Understanding what shares it, and what actually consumes it, is most of the battle.
One quota, three products
Gmail, Google Drive, and Google Photos draw from a single pool. A large Drive folder shrinks the room available for mail, and a photo library backing itself up in the background does the same thing. When people say “Gmail is full”, the cause is often sitting in one of the other two.
Two things do not count against your own quota. Files in Drive that someone else owns and shared with you count against their storage, not yours. And mail that has been deleted and has aged out of Trash is genuinely gone.
Everything else in Gmail counts, which catches people out: archived mail in All Mail, Sent, Drafts, Spam, and Trash all occupy quota. Archiving a message does not reclaim a single byte. It only moves it out of your inbox view.
Attachments are the whole story
An ordinary text or HTML email is small: a few kilobytes to a few tens of kilobytes. Ten thousand newsletters might amount to a couple of hundred megabytes. A single message carrying a phone video can be larger than all of them put together.
Attachments are also bigger in the mailbox than they are on disk. Mail cannot carry raw binary, so attachments are base64-encoded, which inflates them by about a third. A 9 MB photo arrives as roughly 12 MB of stored message. This is why a larger:10M search turns up mail whose attachments you remember as smaller.
Across every cleanup Clear My Inbox has run, the mean message size works out to roughly 44 KB, far above what a typical newsletter weighs. That gap is attachments pulling the average up. The usage stats page shows how that figure is derived and what it does not prove.
The practical consequence: if you are trying to get back under the limit, deleting by size beats deleting by count every time.
Search operators that find the heavy mail
Gmail has no sort-by-size. The search box is the substitute, and it is a good one. Type any of these into Gmail directly.
| Operator | What it matches |
|---|---|
has:attachment | Messages carrying any attachment. The single highest-yield filter for storage. |
larger:10M | Messages over 10 MB in total size, attachments included. Change the number freely: larger:25M, larger:5M. |
older_than:1y | Older than a year. Also takes d and m, as in older_than:30d or older_than:6m. |
category:promotions | Everything Gmail filed under the Promotions tab. Also social, updates, and forums. |
in:anywhere | Includes Spam and Trash, which a normal Gmail search skips even though both count against your quota. |
filename:pdf | Matches on attachment filename or extension. Try mp4, zip, psd, dmg. |
from:newsletter@example.com | One sender. Narrow to a domain with from:example.com. |
is:unread | Mail you never opened. Pairs well with an age filter. |
They combine, and combining is where the leverage is. A search for has:attachment larger:10M older_than:2y returns large mail old enough that you almost certainly do not need it. Add in:anywhere to sweep Spam and Trash in at the same time. Start with larger:25M to see the worst offenders first, then work down.
Once a search is showing what you want, tick the checkbox above the results and Gmail offers to select every conversation matching the search, not just the page in front of you. That is how you act on thousands of messages at once.
Deleting does not free space immediately
Deleted mail goes to Trash and sits there for 30 days before Gmail removes it. For those 30 days it is still occupying your quota. If you are over the limit and need room now, empty Trash yourself after deleting.
Spam works the same way and is worth a look on its own. It also auto-deletes after 30 days, and a neglected Spam folder can hold a surprising amount.
Even after Trash is empty, the storage figure Google shows you can take a while to catch up. The space is released; the number on the screen lags. Do not panic and delete another few thousand messages because the bar has not moved yet.
What happens when you hit the limit
Gmail stops accepting new mail. People writing to you get a bounce message back, so the failure is not silent on their end, but you will not see what you missed. Drive uploads and Photos backups stop as well. Your existing data stays where it is, and normal service resumes once you are back under the limit.
Doing it by hand, and when that stops working
Most of this is genuinely doable yourself, for free, in an afternoon. Run a few size and age searches, select all matching conversations, delete, empty Trash. If you want a walkthrough of that manual route, our parent studio wrote one up: Apex Software Engineering's guide to freeing up Gmail space.
Where the manual route gets tedious is breadth. You are running one query at a time, Gmail will not tell you how much storage any category is worth before you delete it, and the newsletters that caused the problem keep arriving after you finish. That is the gap Clear My Inbox fills: it runs the whole set of queries, estimates the size behind each category so you can decide what is worth deleting, and empties Trash at the end. Nothing is deleted before you approve it.