Free Online Image Converter

Image conversion is the process of translating a picture from one file format to another — say, from a JPEG snapshot into a lossless PNG, or from an iPhone HEIC into a universally-supported JPG. It sounds simple, and for a lot of tools it just is: pick a file, pick a target, download the result. What most tools don't tell you is that every conversion involves trade-offs, and those trade-offs directly affect image quality, file size, transparency, and how the image behaves on the web, in print, or inside a design tool.

Getting a conversion right means understanding what the source format actually stores, what the target format can preserve, and what gets thrown away in between. This overview covers the underlying mechanics so you can make deliberate choices rather than hoping the default settings work out.

Lossy vs. lossless — the choice that matters most

Every image format falls into one of two camps. Lossy formats (JPG, WebP, HEIC, AVIF) discard visual information you're unlikely to notice, then compress what's left aggressively. That's why a 12-megapixel photo can land in a 2 MB JPG instead of a 20 MB raw. Lossless formats (PNG, TIFF, BMP, WebP-lossless) preserve every pixel exactly as-is, at the cost of much larger files.

As a rule: photographs go to lossy because JPEG-family compression is calibrated to human perception. Screenshots, illustrations, diagrams, logos, and anything with sharp edges or flat colour blocks go to lossless because lossy compression introduces visible ringing and haze around those edges.

The common formats at a glance

Colour, transparency, and metadata — what survives the trip

Two files can have the same visible pixels and still differ in ways that matter. A conversion tool preserves — or drops — these three things:

• Colour profile. sRGB is the universal web default. Adobe RGB and ProPhoto have wider gamuts, but if the profile is stripped during conversion, colours may shift on-screen.
• Alpha channel. PNG, WebP, and TIFF carry transparency. JPG and HEIC do not — converting a transparent PNG to JPG will flatten transparency onto a white (or configurable) background.
• EXIF metadata. Camera model, GPS coordinates, and capture time live inside JPG and HEIC files. Uploading a JPG to social media without stripping EXIF exposes location data. Most iFormat conversions preserve EXIF by default; you can strip it explicitly if privacy matters.

Choosing a target format — a short decision tree

• Delivering to a website in 2026? Convert to WebP if you support browsers back to 2020, or AVIF if you're modern-only. Both cut file size roughly 30% versus JPG at equivalent quality.
• Sending to a print shop? Convert to TIFF (or high-quality JPG if the print house asks). Preserve the source colour profile.
• Sharing an iPhone photo with a Windows or Android user? Convert HEIC to JPG. HEIC support on non-Apple systems is spotty.
• Uploading a logo or icon to a design tool? Use PNG for raster or SVG for vector. Never JPG — the compression artifacts show around sharp edges.
• Compressing for email? JPG at 75% quality is nearly always the smallest usable option.

Where lossy compression hides its damage

Every time a lossy format is decoded and re-encoded, quality drops. This "generation loss" stacks: converting a JPG to WebP and back three times will visibly degrade the image, even though each individual step looks fine. If you'll process an image multiple times — editing, resizing, converting — keep a lossless copy of the original and use it as the source each time.

The other trap is over-compression. JPG at 40% quality shows blocky artifacts in flat areas and ringing around edges. Most humans can't tell 80% quality from 100%, but 60% is usually where the degradation becomes obvious on a good display.

What every iFormat image converter does the same way

All the tools listed below share the same processing pipeline: uploads are TLS-encrypted, files are processed on isolated per-request workers, results are available immediately, and both the upload and output are permanently deleted within 30 minutes. No ads, no third-party trackers, no watermarks on paid tiers. Where the conversion can run entirely in your browser (basic format swaps, thumbnails, colour-space changes), we do that — the file never leaves your device.