How do I uncorrupt a corrupted SD card?

Having a corrupted SD card can be very frustrating.important data stored on the card suddenly becomes inaccessible, and you may not know how to fix it. Fortunately, in many cases it is possible to recover data from a corrupted SD card and get it fully functioning again. This guide will walk you through the steps for diagnosing and resolving SD card corruption issues.

What causes an SD card to become corrupted?

There are a few common causes of SD card corruption:

  • Improperly removing the card from a device while it’s still writing data
  • Physical damage to the card from drops, bends, water, etc
  • Power outages or device crashes while the card is being accessed
  • Malware or viruses infecting the card
  • General degradation of the card after prolonged heavy use

These issues can damage the file system on the SD card, making it unreadable by your computer or device. The good news is the actual data is likely still intact until it gets overwritten with new data.

Step 1: Stop Using the Card

As soon as you realize your SD card is corrupted, it’s important to stop using it immediately. Any new writes to the card could overwrite your existing data and make recovery impossible. Eject the card properly from your computer or device and do not attempt to add or modify any files on the corrupted card.

Step 2: Try the Card in a Different Device

Before going through recovery efforts, try inserting the corrupted card into a different device like a phone, tablet, or camera. Occasionally the card may have issues being read only by a specific device. If it mounts successfully on a different gadget, you may be able to directly copy your files from it before pursuing further troubleshooting.

Step 3: Run CHKDSK

If the card is not recognized by any device, try running CHKDSK from the command prompt. CHKDSK analyzes the file system issues and attempts to repair them. To run it:

  1. Insert the SD card into your computer’s card reader
  2. Open the Command Prompt app
  3. Type “chkdsk X: /f” where X is the drive letter of your SD card
  4. Press Enter and let CHKDSK run; this could take a while for large cards

With luck, CHKDSK will be able to repair the file system corruption and make your files accessible again. You can then copy all the data off the card to a safe location before reusing it.

Step 4: Try Data Recovery Software

If CHKDSK is unable to get your files back, your best recourse is a dedicated data recovery program. These tools scour the raw data on the SD card and piece together recoverable files. Some popular free options include:

  • Recuva
  • TestDisk
  • Photorec

For the best results, go with a premium recovery suite like Disk Drill, Recoverit, R-Studio, or EaseUS. While free software can work, the advanced scanning algorithms and features of paid tools give you a better chance of getting back all your data.

To use SD card recovery software:

  1. Download and install it on your computer
  2. Insert the corrupted card into your card reader
  3. Select the SD card drive within the recovery software
  4. Choose a scan type (quick scan for deleted files, deep scan for formatted data)
  5. Preview found files, select those you want to recover
  6. Designate a new folder to save the recovered data

Performing data recovery takes time and needs to happen before you reformat or reuse the card. But data recovery software allows extracting even severely corrupted files from SD cards when all else fails.

Step 5: Reformat the Card Using SD Formatter

After recovering all possible data, the next step is wiping and reformatting the SD card to fix any lingering corruption issues. This prepares the card to store new files again. Use the free SD Formatter utility designed specifically for SD cards. SD Formatter will fully erase data in a way optimized for the SD architecture.

To reformat your card:

  1. Download and install SD Formatter (available for Windows and Mac)
  2. Insert your SD card into the computer
  3. Open SD Formatter and select the card drive
  4. Click “Format” to wipe the card (this takes a few seconds)

Once completed, you can begin using your SD card again. Any leftover corruption is eliminated, though keep in mind other physical damage could cause issues again later.

Tips to Avoid SD Card Corruption

Corruption often blindsides users, but you can reduce the chances of it occurring by:

  • Always ejecting the card properly before removal
  • Sticking to reputable high-endurance SD card brands
  • Avoiding very low quality unbranded cards
  • Being extra careful when directly editing files on the card
  • Regularly backing up important card data to your computer or cloud storage
  • Not exposing cards to liquids, extreme heat or other hazardous conditions

When to Discard and Replace a Corrupted Card

If an SD card gets corrupted frequently or stops working outright, it may be time to replace it. Excessive read/write cycles degrade flash memory cards over time. Continued corruption could mean the storage lifespan has been exceeded.

You can run software like H2testw to analyze the card and check for faults. But consider getting a new card if corruption persists after formatting, or the card has become very slow.


SD card corruption can seem catastrophic at first, but luckily there are ways to address it. Stop using the card immediately after it becomes corrupted, then try it in other devices or run disk utilities. If that doesn’t work, use data recovery software to extract your files before reformatting the card. This should fix most corruption issues, but replacements may be needed for cards that are too far gone.

Back up your data regularly and handle SD cards with care to help avoid corruption in the first place. But even if the worst happens, this guide gives you the steps needed to recover from a corrupted card.

Questions and answers

What is an SD card?

SD cards, short for Secure Digital cards, are non-volatile storage devices used in many portable devices like cameras, phones, and tablets. They are flash-based memory cards that retain data when power is turned off. SD cards come in different sizes and speeds for various uses.

What causes an SD card to get corrupted?

Common causes of SD card corruption include improper ejection before removing the card, physical damage, malware, device crashes while writing data, or general wear after prolonged heavy usage. File system damage prevents proper access to the data.

Can you fix a corrupted SD card?

Yes, in many cases SD card corruption is fixable. Try running disk utilities like CHKDSK, use data recovery software, and reformat the card. This can clear up file system issues. If corruption persists, the SD card may need to be replaced.

How do I recover data from a corrupted SD card?

Use data recovery software like Recuva, TestDisk, Photorec, or premium tools like Disk Drill to extract recoverable data from a corrupted card. It scans the raw data to restore what it can before reformatting.

Is it safe to reuse a corrupted SD card after formatting?

In most cases, reformatting an SD card after corruption will fix issues and make it safe for reuse. However, if problems keep occurring, it likely means the card has reached its end of life and should be replaced.

How can I prevent an SD card from getting corrupted?

Always eject SD cards properly before removal, avoid low quality cards that are prone to issues, limit exposure to extreme conditions, and regularly back up your data. Handling the cards carefully reduces the chance of file system corruption.

Some sample tables that could be relevant for this article:

SD Card Brand Reliability Rating
SanDisk Excellent
Sony Very Good
Samsung Good
Kingston Average
No-Name Cards Poor
Recovery Software OS Compatibility Price
Recuva Windows only Free
TestDisk Windows, Mac & Linux Free
Disk Drill Windows & Mac Paid
Recoverit Windows & Mac Paid