写真で位置情報が漏洩している. それを止める方法は次のとおりです.
I checked a photo from my phone last week. The EXIF data showed my GPS coordinates down to the meter, the exact time (3:17 PM on a Tuesday), my phone model, and which direction I was pointing the camera. Two days earlier I had posted that same photo in a classifieds ad.
Most people don’t realize this because the big platforms strip metadata automatically. Instagram removes it. Facebook removes it. But Craigslist doesn’t. Most forums don’t. Signal and WhatsApp pass files through untouched. Email attachments carry everything.
The fix takes three seconds: run your photos through an EXIF eraser before sharing. The question is whether to use a browser based tool or download desktop software. The answer depends on how many photos you’re handling and whether you trust a browser.
EXIFデータとは?
EXIF stands for Exchangeable Image File Format. It’s metadata that every digital camera and phone embeds in every JPEG: GPS座標, timestamps, カメラのモデル, lens settings, and often a thumbnail of the original image. Think of it as a receipt stapled to your photo that tells anyone who looks exactly where and when it was taken.
This data isn’t hidden. Right click any photo you’ve downloaded, open Properties (Windows) or Get Info (Mac), and the GPS tab shows a pin on a map if location data is still attached.
Online EXIF erasers: browser tools that work in seconds
Online EXIF removal tools are web apps. You open a browser, drag in a photo, and download a clean copy. No installation, no updates, no local storage.
exifaudit.com handles this well. Upload a photo and it shows every metadata field embedded in the file before you wipe it. GPS座標, camera info, edit history, embedded thumbnails, all of it. That audit step is what makes it a privacy tool rather than a blind converter.
Good online EXIF erasers process files locally in your browser via JavaScript. They never upload to a server. Bad ones upload first. The difference is in the privacy policy. ExifAudit is no log and client side, so your files stay on your machine.
Online tools aren’t built for bulk work. If you need to clean 5,000 photos from a shoot, a browser tab is the wrong tool. But for scrubbing a photo before posting on Reddit, listing on Facebook Marketplace, or sharing in a group chat, they’re faster than launching a desktop application.
Desktop EXIF software: for offline processing and bulk editing
Desktop metadata removal is a different category. ExifTool, the free command line tool by Phil Harvey, can strip or edit metadata on tens of thousands of images in one go. Adobe Bridge and Lightroom include metadata panels for selective field editing.
Desktop EXIF editors make sense when:
- Your files can’t leave your local machine for compliance or security reasons.
- You’re processing a wedding gallery or product catalog with thousands of images.
- You need to edit specific fields rather than wipe everything. Keep the copyright tag, remove GPS coordinates, add your own contact info.
The tradeoff is friction. ExifTool means opening a terminal. Desktop apps mean sitting at your desk. And for most people, metadata removal is something they do a few times a week, not all day.
Online vs. デスクトップ: pick based on volume
If you’re a photographer working with hundreds of images per session, use desktop EXIF software. You need batch processing and you probably already have the tools.
If you’re anyone else, use an online EXIF eraser. It takes three seconds, works from any device, and the good ones show you the metadata before removing it so you understand what your phone has been recording.
What matters is building the habit. Most photo privacy leaks aren’t sophisticated attacks. They’re people uploading pictures to sites that don’t strip EXIF, not knowing their location is embedded in the file. Check before you post.
