Convert PNG to JPG — drastically reduce file size

Converting PNG to JPG is one of the most common image tasks — and one of the most commonly done wrong. PNG is a lossless format with transparency support, originally created as a patent-free successor to GIF. JPG is lossy, has no transparency and was built for photos. Anyone converting PNG to JPG should understand what they gain — and what they give up. What you gain. For a classic photo mistakenly saved as PNG, conversion typically shrinks the file to 10–30% of the original. A 5 MB photo PNG becomes a visually identical 500 KB JPG. For email attachments, web embedding and platforms with size limits this is a massive win. What you lose. First, transparency. JPG has no alpha channel — transparent areas are replaced with a background color (default white; configurable in the JNRT Pixel converter). If your PNG is a logo on a transparent background and you embed the resulting JPG on a dark website, you will see an ugly white rectangle around the logo. Second, pixel fidelity. JPG creates visible "ringing artifacts" around fine hatching, hard edges or text. Logos and diagrams suffer; photos rarely do. Rule of thumb. If the source PNG is a photo, conversion to JPG almost always pays off. If it is a graphic with hard edges (logo, diagram, screenshot, pixel art), stay on PNG or switch to WebP-Lossless — both preserve pixel fidelity, and WebP is usually 20–40% smaller than optimized PNG. Quality choice. This converter uses quality 85 by default — conservatively safe: no visible loss, good file size. For aggressive compression go down to 75–78 (web sweet spot). For maximum safety — e.g. if the JPG will be processed further — go up to 90. Multiple files at once. You can drop any number of PNGs into the converter; they are processed sequentially and packaged as a ZIP for download. A normal laptop handles 50–100 images per minute — typical case: optimizing an entire smartphone photo folder for cloud backup. Privacy. Like all JNRT Pixel tools, this converter runs entirely in your browser. No file is uploaded. You can verify this live in DevTools (F12 → Network tab) during conversion. Practically: confidential content (family photos, job application photos, business imagery) stays structurally private. Alternative recommendation. If your goal is "web optimization" and not specifically "JPG", use the Multi-Format Compare instead. It renders the same PNG simultaneously as JPG, WebP and AVIF — WebP or AVIF are usually 25–50% smaller than JPG at identical quality. For modern browser targets (which covers 95% of cases in 2026), WebP is almost always the better choice than JPG. Detailed background in the article PNG to JPG — free, no upload and in the comprehensive compression guide 2026.