When you convert a HEIC photo from your iPhone, the converter asks you to choose between JPG and PNG. It's a simple choice with a clear answer — once you understand what separates the two formats. This guide explains the practical difference and tells you exactly when each format is the right choice.

JPG: The Format Built for Photos

JPG (also written JPEG) has been the standard photo format since 1992. It uses lossy compression — meaning it deliberately discards some image data to achieve smaller file sizes. The data it removes tends to be subtle detail that the human eye is unlikely to notice: fine texture in out-of-focus areas, subtle gradations in shadows, colour information in uniform areas of sky or background.

At quality settings of 85–95%, most people cannot see any difference between a JPG and the original uncompressed image, even in a side-by-side comparison. At the default quality of 92% used by HeicConvert, JPG photos are virtually indistinguishable from the originals for everyday viewing.

JPG files are typically 3–10 times smaller than an equivalent PNG. A typical converted iPhone photo will be 2–5 MB as JPG versus 10–25 MB as PNG. This makes JPG ideal for sharing, email, web publishing, and storage when you have many photos.

Every device, browser, app, and platform supports JPG without any exceptions. It is the closest thing to a universal file format for photos.

What JPG cannot do: it has no support for transparency. If an image needs a transparent background — a product photo, a logo, an illustration — JPG forces that area to be a solid colour (usually white). PNG is required for transparency.

PNG: The Format Built for Precision

PNG (Portable Network Graphics) uses lossless compression — it retains every single pixel of the original image. Nothing is discarded. What you put in is exactly what comes out, with no quality degradation, no compression artefacts, no blurring of edges or banding in gradients.

This pixel-perfect accuracy comes at a cost: PNG files are substantially larger than equivalent JPGs. A photo that's 3 MB as a JPG might be 15–20 MB as a PNG — five to seven times larger. For most photographic use, this extra size provides no visible benefit. A printed or screen-viewed photo at PNG quality looks identical to a high-quality JPG.

Where PNG genuinely excels

• Transparency — PNG is the standard format for images with transparent areas. Logos, icons, product cutouts, overlays — any image that needs to sit on a different background without a white box around it needs PNG (or SVG).
• Screenshots and screen graphics — Text rendered at screen resolution benefits enormously from lossless compression. JPG compression creates visible artefacts around letter edges; PNG preserves them sharply.
• Images before editing — If you plan to open a photo in Photoshop, Figma, or another editor, make adjustments, and re-save multiple times, lossless PNG prevents the quality degradation that accumulates with each JPG save. Once editing is finished, you can export to JPG for the final version.
• Logos, diagrams, and illustrations — Flat colour graphics with sharp edges look cleaner in PNG. JPG's compression is designed for the colour complexity of photographs; it handles flat graphics poorly, creating visible halos and colour shifts near edges.

Side-by-Side Comparison

When to Choose JPG

• Sharing photos by email, messaging, or social media
• Uploading photos to Instagram, Facebook, X, or any social platform
• Publishing photos on a website or blog
• Printing photos at home or at a print shop
• Storing large collections of photos efficiently
• Sending photos to someone who needs to open them quickly on any device

When to Choose PNG

• The image contains or needs transparent areas
• You're saving a screenshot or screen recording frame
• You plan to edit the image further in Photoshop, Figma, or another tool
• The image is a logo, diagram, infographic, or flat illustration
• You need pixel-perfect accuracy for print pre-press work

Converting HEIC iPhone Photos: Which Should You Pick?

For the vast majority of converted iPhone photos, JPG is the right choice. iPhone photos are photographs — JPG compression is designed for exactly this type of content. At 92% quality, the output is visually indistinguishable from the original HEIC, at roughly a quarter the file size of a PNG equivalent.

Choose PNG when you specifically need lossless quality — for example, if you're converting a photo to edit it in professional software and want to preserve every detail before any editing changes are applied.