HEIC to DNG Converter

About HEIC

HEIC (High-Efficiency Image Container) is the default photo format on every iPhone and iPad since iOS 11, released in 2017. Apple adopted it to replace JPEG after nearly four decades — not for aesthetic reasons, but for pure efficiency. A 12-megapixel photo that takes 3.5 MB as a JPEG typically occupies just 1.5–2 MB as HEIC, with no visible difference in quality.

The compression comes from HEVC (H.265), the same video codec that makes 4K streaming practical on mobile connections. HEVC analyzes the image in chunks and encodes spatial patterns more efficiently than JPEG's block-based DCT algorithm. The result is 10-bit color depth — compared to JPEG's 8-bit — which means smoother gradients and more accurate shadow and highlight detail, particularly in portrait and landscape photography.

HEIC also functions as a container, not just a codec. A single .heic file can hold a burst sequence, a Live Photo (the still frame plus the short video clip), or a portrait-mode photo with its depth map intact — all in one file. JPEG cannot do any of this.

The compatibility problem

HEIC's efficiency comes at a cost: it requires hardware support and licensed software to decode. Windows does not open HEIC files natively. Most Android devices cannot display them. Chrome, Firefox, and Edge do not render HEIC in the browser. The majority of websites, online forms, and file-upload services expect JPEG or PNG. Print labs, stock photo sites, Google Drive's web viewer, Facebook, Instagram, and Microsoft Office all work with JPEG — not HEIC.

If you've ever emailed an iPhone photo to a Windows user and had them tell you it won't open, or tried to upload a photo and gotten a "file type not supported" error, HEIC is why.

What happens during HEIC to JPG conversion

Converting HEIC to JPEG is a decode-then-re-encode process. The HEVC-compressed data is decoded to a raw pixel grid, then re-encoded using JPEG's algorithm. Both formats are lossy, so this is technically a second lossy compression step. In practice, at quality settings of 82% or higher, the difference is imperceptible — even at full zoom on a high-resolution monitor. If you need to compare, open the original HEIC on an iPhone or Mac and the converted JPEG side-by-side; at typical sharing sizes, they are visually identical.

EXIF metadata — including the date, camera settings, and GPS coordinates — is preserved in the conversion unless you explicitly strip it. The primary still frame is extracted and converted. Live Photo motion clips, depth maps, and HDR metadata are not carried into the JPEG; JPEG has no container for them.

File size after conversion

A 2 MB HEIC photo typically becomes a 3–5 MB JPEG at 85% quality. This isn't a flaw in the converter — it's the fundamental difference in codec efficiency. HEIC is the more compact format. Converting to JPEG expands the file because JPEG needs more bytes to represent the same visual data. If final file size matters, consider converting to AVIF instead: AVIF is an open-standard successor to HEIC with comparable compression and broad browser support in 2024 and beyond.

The GPS and privacy consideration

iPhones embed precise GPS coordinates in every photo's EXIF data by default. When you convert HEIC to JPEG, that location data transfers to the new file. If you're uploading converted photos to a public website, a social media profile, or a forum, anyone who downloads the image and reads its EXIF data can see exactly where it was taken — your home, your workplace, your children's school.

Before sharing converted photos publicly, strip the EXIF location data. After conversion, run the JPEG through at-use.com's EXIF metadata remover to clear GPS tags before uploading anywhere public.

When to keep HEIC

If you live entirely within Apple's ecosystem — shooting on iPhone, editing on Mac, storing in iCloud Photos, viewing on Apple TV — HEIC is the right choice. Apple's apps handle it natively, you preserve more visual data in less storage, and Live Photos stay intact. Convert when you need to cross the boundary: sharing with Windows or Android users, uploading to a website, submitting to a print lab, using in a presentation, or archiving in a format that will open on any device in ten years.

About DNG

DNG (Digital Negative) is an open RAW format published by Adobe in 2004 as a universal, future-proof alternative to manufacturer-proprietary RAW formats like CR2, NEF, and ARW. It is used in two distinct contexts: (1) as a native capture format by cameras and smartphones — Google Pixel (via the Android Camera API raw output), Adobe Camera on iOS, Leica M-series, Ricoh GR series, Pentax K-series, and Hasselblad cameras — and (2) as a conversion target, with Adobe Lightroom's "Convert to DNG" function repackaging proprietary RAW files into the open DNG format for archival.

Like other RAW formats, DNG stores unprocessed sensor data before white balance, tone curve, or any color science is applied. The key advantage over proprietary formats is longevity: DNG is a published ISO-standard container format that software will continue to support regardless of camera manufacturer decisions. This converter supports both camera-native DNG and Lightroom-converted DNG files.

When DNG to JPG makes sense

DNG files — whether from a Google Pixel, a Leica, an Adobe Camera export, or a Lightroom DNG archive — are not viewable outside dedicated RAW software. For sharing, delivery, or web publishing, JPG is required. This converter handles all DNG source types in a single upload.

About this conversion

ufraw-batch decodes the DNG sensor data using auto white balance and a linear tone curve. For smartphone-origin DNG files (Pixel, Adobe Camera on iOS), the output is a neutral, single-exposure RAW decode without any computational photography processing — no HDR fusion, no AI sharpening, no Night Sight enhancement — that the originating app would apply. For camera-origin DNG files (Leica, Ricoh, Pentax), the output similarly reflects the raw sensor data without camera-specific color science. The output is a technically correct starting point, not a finished image. For output that matches the phone's native JPEG processing, export directly from Google Photos (for Pixels) or from Adobe Lightroom.

File size note

DNG file sizes vary widely depending on source. Smartphone DNGs from Pixel 8 Pro (50 MP sensor) can reach 25–80 MB uncompressed — well above this converter's 20 MB upload limit. DNG files converted from existing DSLRs via Lightroom retain the size of the source RAW. For large Pixel DNG files, use the phone's native JPEG export in Google Photos. For Lightroom-converted DNGs, use lossless compression in DNG conversion settings to reduce file size before uploading.