How to Format an SD Card: Camera, Phone and PC Guide

Formatting an SD card wipes it clean and sets it up with a fresh file system, so your device can read and write to it reliably. It takes less than a minute, and it can fix many common card problems.

You should format an SD or microSD card:

• When it's brand new, so it's set up for the device you'll use it in.
• When you move it to a different device, such as from a phone to a camera or dash cam.
• When you've copied your photos or videos off it, to start each shoot or trip with a clean card.
• When it shows errors, such as "card not readable", missing files or a full card that looks empty.

This guide shows you how to format an SD card in a camera, dash cam or security camera, on an Android phone, on a Windows PC and on a Mac. Choosing a new card? Read our guide, What Do You Need to Know About Memory Cards?

Formatting erases everything on the card. Check these three things first:

1. Back up your files. Copy any photos, videos or documents you want to keep to a computer or cloud storage. On a computer, you'll need a card slot or a USB SD card reader.
2. Check the lock switch. Full-size SD cards have a small slider on the left edge. If it's pushed down to "Lock", the card is write-protected and won't format. Slide it up. MicroSD cards have no switch, but a microSD-to-SD adapter does.
3. Know your card's size. The capacity, such as 32GB or 128GB, decides which file system to pick on a computer (see the next section).

Quick format or full format? A quick format clears the card's file table in seconds, which is fine for everyday use. A full format (untick "Quick Format" on Windows) also checks the whole card for faulty areas. It takes longer but is worth doing if a card has been playing up.

When you format on a computer, pick the file system that matches your card's capacity. Cameras and phones choose automatically.

Avoid NTFS for SD cards. Windows reads it, but most cameras, phones and dash cams don't, and Macs can't write to it.

Some devices, such as certain dash cams and security cameras, insist on FAT32 even for larger cards. If your device's manual says so, follow it. Better still, format the card in the device itself.

Formatting in the camera you'll use is the best option. The camera sets the card up exactly how it wants, which helps prevent write errors.

1. Make sure the battery is well charged, so the camera doesn't switch off mid-format.
2. Insert the card and switch the camera on.
3. Press Menu and open the Setup tab, often shown as a spanner or toolbox icon.
4. Select Format or Format card.
5. Choose the card slot if your camera has two.
6. Confirm with OK, then wait for the camera to finish.

Menu names vary slightly between Canon, Nikon, Sony, Fujifilm and other brands. If you can't find the option, search your camera's manual for "format".

Dash cams and security cameras record non-stop, which puts more wear on a card. Format the card every few weeks to keep recordings reliable.

• Dash cams: most have a Format option in the settings menu on the screen or in the companion app. Some brands remind you to format regularly. See our beginner's guide to dash cams for more tips.
• Wi-Fi security cameras: format from the camera's app. It's usually under the camera's settings, in a section called Storage, SD card or Recording.

For these devices, choose a card rated for continuous recording, often labelled "High Endurance".

Most Android phones with a microSD slot can format the card in a few taps. iPhones don't have a card slot, so use a computer instead.

Samsung Galaxy phones

1. Open Settings.
2. Tap Battery and device care (called Device care on some models), then Storage.
3. Swipe or tap across to SD card.
4. Tap the three-dot menu, then Format.
5. Tap Format again to confirm.

Other Android phones

1. Open Settings, then Storage.
2. Tap your SD card.
3. Tap the three-dot menu, then Format (you may need to tap Storage settings first).
4. Confirm to erase the card.

Menu names differ between brands and Android versions. If you can't find it, search "format" in the Settings search bar.

Portable or internal storage? Some phones ask how you want to use the card. Choose portable storage if you'll move the card to a computer or another device. Internal storage locks the card to that phone, and it won't work anywhere else until you format it again.

Insert the card into your PC's card slot or a USB SD card reader. For a microSD card, use a microSD-to-SD adapter or a reader with a microSD slot.

1. Open File Explorer and click This PC.
2. Right-click the SD card (it usually shows as "SDHC", "SDXC" or "Removable Disk") and select Format.
3. Under File system, choose FAT32 for cards up to 32GB or exFAT for 64GB and above.
4. Leave Allocation unit size on Default.
5. Type a name under Volume label if you want one.
6. Tick Quick Format for a fast wipe, or untick it for a full check.
7. Click Start, then OK to confirm.

Double-check you've picked the right drive. Formatting the wrong one, such as a USB stick or external hard drive, will erase it.

Windows' built-in Format window usually won't offer FAT32 for cards over 32GB. If a device insists on FAT32, format the card in that device instead.

Macs format SD cards with the built-in Disk Utility app. Insert the card into your Mac's SD slot or a USB-C card reader, then follow Apple's steps:

1. Open Disk Utility. Press Cmd + Space and type "Disk Utility" to find it.
2. Choose View > Show All Devices from the menu bar.
3. In the sidebar, select the SD card itself (the top-level device, not the volume indented beneath it).
4. Click Erase in the toolbar.
5. Type a name of up to 11 characters.
6. Under Format, choose MS-DOS (FAT) for cards up to 32GB or ExFAT for larger cards.
7. Under Scheme, choose Master Boot Record, which works best with cameras and other devices.
8. Click Erase, then Done.

Avoid the Mac-only formats such as APFS and Mac OS Extended. Cameras, phones and Windows PCs can't read them.

If a card still won't format after all this, it has probably failed. SD cards wear out over time, especially in dash cams and security cameras. Replace it rather than risk losing important recordings.

Formatting an SD card takes under a minute and keeps it working reliably. Back up your files, then format in the device you'll use the card in whenever you can. On a computer, choose FAT32 for cards up to 32GB and exFAT for larger cards.

Need a new card or a way to connect one to your computer? Browse Maplin's range of memory cards and SD card readers.