The Ultimate Guide to Image Conversion
Not having the correct image format for a task can result in everything from minor annoyances to serious business complications. Many websites accept only certain types of image formats, and those websites range from social media platforms to identity verification sites required for banking.
Unfortunately, converting an image from one format into another on your computer often requires specialized paid software. Even if the software is free, the available tools are typically complicated to learn, which is a ton of hassle to go through just to convert an image!
Another reason for requiring image format conversion is that sometimes your computer simply can't read an image produced on a different operating system. For example, certain Apple formats can't be viewed on Windows computers without special software.
That's why we developed ImageConverter.com, which converts images into all the most common formats.
Below, we explain how to use the tool, as well as what the different image formats are and why they exist.
No Software Needed for Highly Secure Image Conversion
Other image conversion tools also exist, but these tools typically send your file to a server somewhere to convert your image. That server might be in the United States or in Russia. You don't know. It might be a secure server where files are encrypted, or a completely insecure server running in someone's basement.
None of the above is a joke. Unless you're dealing with a well-known and established business, anyone can start a website anywhere, and the above scenarios are all entirely possible.
That's a risk for all images, but especially when uploading sensitive documents such as ID and passport images required for identity verification. No guarantee exists that your passport or ID image won't be stored indefinitely on some insecure server, potentially leading to identity fraud in the future.
In other cases, you might just not want certain images to be shared with others, such as personal family photos, or photos with your children's faces on them.
That's why we developed ImageConverter.com to run the entire conversion in your browser, meaning the image never leaves your computer.
This is only possible because of recent advances in technology, which allow sophisticated code to run directly in your browser, doing away with the need for server communication altogether.
When using ImageConverter.com, your images are perfectly secure because they never leave your computer.
Step-by-Step Guide: How to Use ImageConverter.com
The first step is to select the source image from your device. If you're on a mobile phone or tablet, click the "Select Files" button. If you're on a device that uses a mouse or trackpad, such as a laptop or desktop computer, you can drag images directly onto the conversion box.
ImageConverter.com automatically detects the source format of your selected image. For example, in the screenshot below, we chose a JPEG image, which is why the "JPG" button in the "Target Format" section is grayed out. (JPEG and JPG are the same format. At the end of this guide, we explain why two names exist for it.)
If you upload multiple images with different formats, then you can select any target format as the final format for all images.
You can convert as many images at a time as you want. However, keep in mind that the speed of conversion depends on:
- Your device's capabilities
- The size of the image being converted
Because all conversions occur directly on your device, the amount of memory and processing power it has determines how fast the conversions will take. If you're on a mobile device and need to convert very large images, we recommend doing a maximum of only two or three at a time. On a desktop computer with more memory and processing power, you can do more.
When the conversion is complete, the "Convert" button changes to a "Save All" button, which lets you save all images with a single click. Each image also has a green "Save" button that you can click to save each image individually.
What Image Types Does ImageConverter.com Convert?
ImageConverter.com supports outputs in the most common formats (JPEG, PNG, WebP, and AVIF) and a much wider variety of input formats.
Let's look at these formats and what they are:
HEIF (High Efficiency Image File Format)
HEIF is a high-efficiency "container" format that can store various types of multimedia files, such as video, audio, and images. You can think of it as a digital envelope that can hold one or more images, along with extra information, such as the photo's location or even a short video clip.
For example, an HEIF container can store all the edits associated with an image, along with the unedited image. This is one of the ways smartphone apps can let you restore an image to the original even months after editing it.
HEIF can also store image sequences, also known as "Live" images on an iPhone.
All major operating systems support HEIF images. However, older operating systems, such as Windows 10, might need additional software to view the image.
No browser can display them natively, meaning that you must convert them to one of the browser-friendly formats (JPEG, PNG, WebP, etc.) to view them on a web page.
HEIC (High Efficiency Image Container)
HEIC is Apple's version of the HEIF image format and has become the standard image format for all Apple devices.
Unlike the HEIF container, which can store images of different formats, the HEIC format only stores images encoded using the HEVC (High Efficiency Video Coding) codec.
A "codec," short for "coder/decoder," is software for digitizing multimedia signals. Codecs encode audio, video, and images into digital data, and also decode it for viewing and listening.
While HEIC files are incredibly efficient, they're not compatible with Windows machines.
Companies must also pay a license fee for implementing HEIC, making it less popular than formats using open standards.
Many websites don't accept uploading an HEIC format, which is why it's necessary to use a tool such as ImageConverter.com to convert HEIC to JPEG or another widely adopted web format.
JPG/JPEG (Joint Photographic Experts Group)
JPEG (or JPG) is the most widely used format for digital photos. The terms JPG and JPEG are interchangeable. The three-letter version exists because older Windows computers required three-letter file extensions.
The format was created by the Joint Photographic Experts Group and released in 1992.
The major breakthrough of JPEG images is that the format allowed images to be significantly compressed without noticeable differences in image quality. It quickly became the most popular format for sharing images online and the default format for many digital cameras.
Despite its age, the JPEG format remains a mainstay of the modern web.
Unfortunately, JPEGs don't support transparency, and some permanent loss of detail does occur at higher compression levels.
GIF (Graphics Interchange Format)
The GIF emerged in 1987, four years before the internet, at a time when users paid for bandwidth per hour. Transferring large files by email chewed up that bandwidth, and computers of the day strained to show large images because of memory constraints.
CompuServe was an internet bandwidth provider and wanted to solve this problem for users by creating an image format that supported compression.
The Graphics Interchange Format file was born.
Unfortunately, CompuServe had inadvertently used a patented compression algorithm, which ended up being both the impetus for the PNG format (discussed below) and the beginning of the end for the GIF's immense popularity.
However, GIFs still dominate the internet in the domain of animated images. The patents used in GIFs expired in 2003 and 2004.
PNG (Portable Network Graphics)
The PNG format is a "lossless" compression format, meaning it doesn't lose any image data when compressing it. This contrasts with the JPEG format, which uses a "lossy" compression method.
PNG's history is an exciting one. It originated in 1995 as a direct response to a sudden legal situation regarding GIFs.
CompuServe had created the GIF format but inadvertently used patented material from Unisys to do it. On December 28, 1994, Unisys and CompuServe reached an agreement that they would charge royalties for any use of GIFs in commercial products.
The internet revolted.
In response, a working group, led by developer Thomas Boutell, was formed to create a replacement format that was better, more extensible, and completely free of patent issues.
The result was the PNG format, which supports transparency and also maintains excellent detail in compressed images.
PNGs are widely used for logos and design work because they maintain sharp edges and high contrast in images, which JPEGs struggle with.
PNGs don't support animation, unlike GIFs.
WebP
WebP was developed by Google and first announced in 2010. It was based on the technology Google acquired when it bought a company called On2 Technologies.
WebP images support both "lossy" and "lossless" compression.
Google's goal was to create a single format that could replace JPEG, PNG, and GIF. Over the next decade, Google added features like transparency and animation. Today, all major browsers support WebP images.
Some "Animated WebP" generators exist online, but GIFs dominate the domain of animated images by far.
BMP (Bitmap Image File)
BMP is an uncompressed image format that maps out every single pixel of an image individually, like a giant digital mosaic. Far more efficient ways now exist to store image data.
Microsoft developed the BMP format in 1987 and built it into every Windows operating system. The format became the default format used in Microsoft's Paint program.
Unfortunately, BMP files are massive, and the JPEG soon dethroned BMP as the preferred image format for the web and photos. PNGs superseded the BMP because they maintained high quality at a much smaller file size.
You'll find BMPs today mostly from legacy applications and software.
BMP files also lack other essential features for professional use, such as the ability to store metadata or to compress images efficiently.
TIF/TIFF (Tagged Image File Format)
TIFF is a high-quality "container" format used primarily in professional industries where image data must remain perfectly intact. It's mainly used in professional printing, publishing, and medical imaging. People use it whenever quality is more important than file size.
Unlike JPEGs, TIFFs don't produce "smudging" when storing massive amounts of detail.
Because they're containers, they can store multiple versions of the same image, such as including a thumbnail version.
TIFFs support compression, giving them an edge over BMP files, whose large size makes them harder to share and store.
AVIF (AV1 Image File Format)
AVIF is the newest major image format. It's already considered the most advanced way to store images because it offers the highest quality at the smallest possible file size.
AVIF was released in 2019 by the Alliance for Open Media, a group that includes tech giants like Google, Apple, Microsoft, and Netflix. It was created to solve the licensing problem of the HEIC format.
AVIF is open-source and royalty-free, meaning anyone can use it for free. It uses the compression technology from AV1, a modern video format designed for high-quality streaming.
ICO (Windows Icon Format)
An ICO file is a specialized image format used specifically for desktop icons in Microsoft Windows. It was created to provide a way for the operating system to display small graphic symbols that represent folders, files, and programs. Initially, these files were very simple and low-resolution, but they have evolved over decades to support the high-definition, colorful icons seen in modern versions of Windows.
Every major operating system and browser supports ICO files.
You can upload any of the above image formats to ImageConverter.com and convert them to JPEG, PNG, WebP, or AVIF.
Summary
The world has many different image types, many of them developed to solve a problem that other types didn't solve. Despite each image format's usefulness, the amount of choice adds complexity for users when trying to do something simple like upload an image to a website.
Existing online conversion services typically lack the necessary security for converting images without sending them to an unknown server, and converting them on your local computer requires specialized software.
Now, with ImageConverter.com, you can convert images for free, and 100% securely inside your own browser.