You’re scrolling through your iPhone settings, trying to figure out why you’re getting that annoying "Storage Almost Full" notification. You tap on General, then iPhone Storage, and there it is. Instagram.
The app itself is only about 200MB or 300MB. But right underneath, there’s a massive number next to Documents and Data. Sometimes it’s 2GB. Sometimes it’s 10GB. If you’re a heavy user, it might be even more. It feels like the app is literally eating your phone from the inside out.
Honestly, it's frustrating. You didn't download 5GB of photos, so where is all that space going?
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What Actually Is Documents and Data on iPhone Instagram?
Basically, "Documents and Data" is a catch-all bucket for everything the Instagram app saves on your iPhone that isn't the core app code itself.
When you download Instagram from the App Store, you get the "App Size." That’s the engine. But as soon as you log in and start scrolling, the app starts building a hoard of files. Think of it like a backpack. The backpack is the app size; everything you stuff inside it—water bottles, snacks, heavy books—is the Documents and Data.
The Cache Hoard
The biggest culprit here is the cache. Instagram is a visual beast. Every time you watch a Reel, look at a high-res photo, or check someone’s Story, the app "pre-loads" that content. It saves a copy of those images and videos to your phone's local memory.
Why? Because if you scroll back up or visit that profile again five minutes later, Instagram doesn't want to waste your data or time downloading it from the server again. It just pulls it from your phone’s internal storage. It makes the app feel snappy, but it kills your free space.
Your Search History and Logs
Every search you perform, every "Explore" page preference, and even the tiny bits of data used to track your interactions for ads—it all lives in this category. These are small files, but they add up.
Drafts and Offline Content
If you have twenty half-finished Reels sitting in your drafts, those are stored in Documents and Data. High-resolution video files are huge. If you’ve got a dozen 4K clips waiting for you to add music and hit "share," your storage usage is going to skyrocket.
The Big Problem: Why iOS Doesn't Have a "Clear Cache" Button
If you’ve ever used an Android phone, you know there’s a beautiful button in the settings that says "Clear Cache." You tap it, the junk vanishes, and the app stays put.
Apple doesn't do that.
For whatever reason, iOS still handles app data with a very "all or nothing" approach. You can't just dive into the Instagram settings on your iPhone and wipe the cache. Apple expects the operating system to manage this automatically when you run low on space, but it rarely does a good enough job. Most of the time, the cache just keeps growing until you take matters into your own hands.
How to Actually Clear the Data Without Losing Your Mind
Since there’s no "Clear Cache" button, you’ve basically got two real options to get that storage back.
1. The "Offload App" Trick
This is the "middle ground" solution. If you go to Settings > General > iPhone Storage > Instagram, you’ll see an option to Offload App.
When you tap this, the iPhone deletes the app itself but supposedly keeps your "Documents and Data." Now, here’s the nuance: while it’s meant to keep your data, many users find that offloading and then reinstalling the app clears out the temporary "junk" cache while keeping your login info and drafts intact. It’s a bit of a gamble, but it’s faster than a full delete.
2. The Nuclear Option (Delete and Reinstall)
If your Instagram is showing 5GB of data, this is the only way to be 100% sure you’re getting that space back.
- Long-press the Instagram icon on your home screen.
- Tap Remove App, then Delete App.
- Go to the App Store and download it again.
When you log back in, you’ll notice that "Documents and Data" has shrunk back down to almost nothing. It will stay small for a few days, but as soon as you start watching Reels again, it will start growing. It’s a cycle.
A Quick Warning on Drafts: If you delete the app entirely, you will likely lose any Reels or posts currently saved in your Drafts folder. These are stored locally on your device, not on Instagram's cloud. Save them to your camera roll before you hit delete.
Why Does Instagram Take Up More Space Than Other Apps?
You might notice that X (formerly Twitter) or Threads doesn't grow nearly as fast. That’s because Instagram’s content is almost entirely high-bitrate video.
Ever since the pivot to Reels, Instagram has become a data-hungry monster. A 30-second Reel can be 50MB. If you watch 100 Reels in a day (which is easy to do), that’s 5GB of video data passing through your phone. Even if the app only caches 10% of that, you’re looking at a massive storage creep over a month.
Can You Stop It From Happening?
You can't stop the cache entirely—it’s how the app is designed to work. However, you can slow it down.
- Turn off "Upload at Highest Quality": Go to your Instagram profile > Settings and Privacy > Media Quality. If this is on, every video you post takes up more space in your drafts and data logs.
- Use "Less Data": In the same Media Quality menu, you can toggle on "Use Less Cellular Data." This prevents the app from pre-loading videos as aggressively when you’re on a mobile network, which can indirectly keep the cache size smaller.
- Stop Saving Original Photos: In your settings, look for "Original Posts." If this is toggled on, Instagram saves a copy of every photo you take with the in-app camera to your iPhone’s library. That’s double the storage usage.
What Happens if You Do Nothing?
If you just leave it alone, eventually iOS will realize you're out of space. When that happens, the system should trigger an automatic cleanup of "temporary files" (which includes the Instagram cache).
But honestly? It's better to manage it yourself. Waiting for the iPhone to do it usually means your phone starts lagging, or your camera stops working right when you want to take a photo because there's "no room."
Summary of Actionable Steps
- Check the Damage: Go to Settings > General > iPhone Storage and see how big Instagram's "Documents and Data" really is.
- Save Your Drafts: If you’re going to delete the app, export any unfinished Reels to your camera roll first.
- Reinstall Periodically: If you use Instagram for more than an hour a day, plan to delete and reinstall the app once every few months to keep the storage under control.
- Monitor Media Settings: Flip the "Use Less Cellular Data" switch to keep the app from being too "helpful" with its pre-loading.
There is no permanent "fix" for Documents and Data on iPhone Instagram because it’s not technically a bug—it’s a feature that prioritizes speed over storage. Until Apple gives us a manual cache clearing tool, the delete-and-reinstall dance is the only way to keep your iPhone breathing.
To get started right now, head to your iPhone Storage settings and see which apps are the biggest offenders. If Instagram is over 2GB, it’s probably time for a fresh install.