Remove Metadata From JPG Files

How a JPG file stores metadata

A JPEG file is a sequence of marker segments. Every marker starts with the byte 0xFF followed by a type byte, and most carry a two-byte length. The picture itself lives in the quantisation tables (DQT), the Huffman tables (DHT), the frame header (SOF) and the entropy-coded scan that follows the start-of-scan marker (SOS).

Metadata lives in the application segments, APP0 through APP15, and in comment segments. They sit near the front of the file, before the image data, which is why a metadata reader can show you a photo's GPS coordinates after downloading only the first few kilobytes.

• APP0 — the JFIF header: pixel density and aspect ratio. Structural, not identifying, so it is kept.
• APP1 — EXIF, identified by the string 'Exif'. Camera, lens, exposure, timestamps, GPS and an embedded thumbnail.
• APP1 (second one) — XMP, identified by an Adobe namespace URL. Editing history, creator, rights, ratings.
• APP2 — the ICC colour profile. Describes the colour space; kept by default so colours do not shift.
• APP13 — Photoshop resources containing IPTC fields: caption, keywords, credit, source, copyright.
• APP11 — JUMBF boxes, used for C2PA content credentials.
• APP3–APP12, APP14–APP15 — vendor blocks from phone makers, plus Adobe's colour transform marker in APP14.
• COM — free-text JPEG comments, written by some export tools and batch scripts.

Why removal from a JPG is lossless here

Because metadata sits in its own segments, removing it is a structural edit rather than an image operation. The tool walks the marker list, skips the segments you want gone, and copies everything else — including the entire compressed scan — byte for byte.

This matters more for JPEG than for other formats, because JPEG is lossy. Every re-save costs quality. A tool that removes metadata by re-encoding gives you a slightly softer photo with new compression artefacts; this one gives you the same photo with fewer bytes of header.

The EXIF thumbnail and the orientation flag

Two JPEG-specific details are worth knowing. The first is the embedded thumbnail: EXIF's second directory holds a small JPEG copy of the image, and some editors update the main image without regenerating it. A cropped photo can therefore ship with a thumbnail showing the uncropped original. Removing EXIF removes the thumbnail too.

The second is orientation. Phones often save the sensor's native landscape frame and set a flag saying how to rotate it for display. Strip the flag and the photo is displayed sideways in many viewers, even though the pixels are unchanged. By default this tool re-writes that single flag on its own, in a 32-byte EXIF block containing nothing else, and tells you it did so. You can turn it off.