Blog ·Guides ·5 min read ·Updated July 8, 2026

How to Choose the Right File Format (Images, Audio, Video & Docs)

File formats are one of those things nobody teaches you, yet you bump into them constantly. Pick the wrong one and you end up with a blurry logo, a 200 MB email attachment, or a document that will not open on someone else’s computer. This is a practical cheat sheet: what to use, when, and why — across images, audio, video, and documents.

The one principle behind every choice

Almost every format decision comes down to a single trade-off: quality and compatibility versus file size. "Lossless" formats keep every detail but are large. "Lossy" formats throw away data you are unlikely to notice, so they are small. Older, universal formats open everywhere; newer, efficient formats are smaller but not supported by every app yet. Once you see a format through that lens, the right pick is usually obvious.

Images

For photos and graphics:

FormatUse it forAvoid it for
JPGPhotos, anything with gradientsLogos, text, transparency
PNGLogos, icons, screenshots, transparencyLarge photos (huge files)
WebPThe web — smallest files, modern browsersOlder apps that cannot open it
SVGLogos and icons that must scale crisplyPhotographs

Audio

For music, voice, and everything in between:

FormatUse it forNotes
MP3Everyday music, podcasts, sharingSmall, plays on everything
WAVEditing, mastering, pro audio inputUncompressed — very large
FLACArchiving music at perfect qualityLossless, about half of WAV
M4A / AACApple ecosystem, streamingEfficient but less universal than MP3

Video & documents

For video, MP4 is the safe universal choice that plays almost everywhere, while WebM is smaller and ideal for websites on modern browsers. If you only need the sound, extract it to MP3.

For documents, PDF is the format to share and print because it looks identical on every device and cannot be easily altered. Keep an editable original (Word, for example) for yourself, and send the PDF. When a document must be preserved for the long term — legal or archival use — PDF/A is the specialised, self-contained version to use.

When in doubt

Default to the widely supported option (JPG, MP3, MP4, PDF) when you are sharing with people or unknown devices, and to the efficient or lossless option (WebP, FLAC, WebM) when you control the environment or need the smallest or highest-quality file. And remember nothing is permanent — you can convert between any of these in seconds with The App Hub Converter if you change your mind.

Frequently asked questions

What is the difference between lossy and lossless?

Lossy formats (JPG, MP3) permanently discard some detail to shrink the file; the loss is usually invisible or inaudible. Lossless formats (PNG, FLAC, WAV) keep every bit of data but produce larger files.

What is the most universal format for each type?

JPG for images, MP3 for audio, MP4 for video, and PDF for documents. These open on virtually any device or app.

Can I convert between formats without losing quality?

Converting into a lossless format never adds quality but preserves what you have. Converting into a lossy format loses a little each time, so always start from the best original you have.

Try it yourself — free

The App Hub Converter runs in your browser: private by default, no sign-up, files auto-deleted.

Open the Converter