Convert JPG to JPEG — Free Online Converter

JPG and JPEG are the exact same image format — Joint Photographic Experts Group — differing only in the file extension. The .jpg extension became common because early versions of Windows (3.1 and DOS) required three-character file extensions, so .jpeg was shortened to .jpg. Modern operating systems support both extensions interchangeably. The image data, compression algorithm (DCT-based lossy), metadata (EXIF), and color model (YCbCr) are identical regardless of which extension is used.

Converting JPG to JPEG is therefore a simple file rename operation. The image data passes through untouched — no re-encoding, no quality loss, no pixel changes. This conversion exists to satisfy software, upload forms, or validation systems that specifically check for the .jpeg extension and reject .jpg, even though the underlying format is identical.

Some file upload systems, CMS platforms, and validation scripts check the file extension rather than the actual file format. A system configured to accept ".jpeg" files may reject a perfectly valid ".jpg" file because the extension check is string-based. Rather than fighting with the system administrator, simply converting the extension resolves the issue instantly.

Certain photography workflows and naming conventions standardize on .jpeg as the canonical extension because it matches the full format name. Photo management software like Adobe Lightroom exports as .jpeg by default, and some photographers rename all their files to .jpeg for consistency. If you receive JPG files from a camera and need them to match your .jpeg naming convention, this conversion handles the batch rename cleanly.