Best File Formats for Online Sharing in 2025
Every time you share a file online — posting a photo to social media, emailing a document, sending an image in a chat — the format you choose affects how well it displays, whether it uploads successfully, and whether the recipient can open it. This guide covers the best format for every common online sharing scenario.
Best Format for Photos on Social Media
For sharing photos on social media platforms (Instagram, Facebook, Twitter/X, LinkedIn, Pinterest), JPEG is the most reliable choice. Every major social platform accepts JPEG, and most automatically re-compress uploads anyway — their algorithms are optimized for JPEG input.
For Instagram specifically: JPEG at 90%+ quality, sized to 1080 pixels on the longest side for square or portrait posts, or 1080×566 for landscape. Instagram's compression is aggressive; uploading a high-quality JPEG gives the platform more to work with and typically produces better results than uploading a lower-quality compressed image.
PNG on social media: Accepted by most platforms, but converted to JPEG automatically for most content (since they serve JPEG to users). The conversion may produce lower quality than if you had uploaded JPEG directly. For graphics, logos, or screenshots with sharp text on social media, PNG input may produce better results because the platform's JPEG conversion handles crisp edges better from a lossless source.
WebP: Not accepted by all platforms and should generally be converted to JPEG before uploading.
Best Format for Documents
For sharing documents — reports, invoices, forms, contracts, presentations — PDF is the universal standard and the correct choice in virtually every case.
PDF preserves formatting exactly across all devices and operating systems. A PDF created on a Windows computer looks identical when opened on a Mac, iPhone, or Android tablet. There are no font substitution issues, no layout shifts, no compatibility problems.
PDF is accepted everywhere: email attachments, business portals, government submissions, legal filings, academic submissions, and corporate workflows all support and often require PDF.
For documents that need to be edited by the recipient, sharing the native format (Word .docx, Excel .xlsx, PowerPoint .pptx) is more appropriate. For final versions, contracts, presentations to clients, or any document where formatting fidelity matters, convert to PDF before sharing.
For very large PDFs, compress them before sharing. A 30-page PDF with unoptimized images can be 50+ MB; compressed with appropriate image settings, the same document is typically 2–5 MB.
Best Format for Photos in Messaging Apps
In messaging apps (WhatsApp, iMessage, Telegram, Signal, Facebook Messenger), JPEG is the safest and most universally accepted format for photos.
All messaging apps accept JPEG. Most also accept PNG and will convert it internally. Some apps (Telegram, Signal) also support WebP for stickers and some image types.
A key consideration for messaging is file size. Most messaging apps have upload size limits (typically 100 MB–200 MB per file for WhatsApp; smaller for some others), and large files take longer to upload and download on mobile connections. Sending a 12 MB smartphone photo when a 300 KB compressed version looks equally good at message view size is wasteful.
For photos taken on smartphones destined for messaging: JPEG is perfect as-is for most sharing. If you want to reduce size before sharing many photos, JPEG at 85% quality reduces file size by 70–80% without visible quality loss at messaging display sizes.
For graphics, logos, or screenshots in messaging: PNG preserves sharp edges better than JPEG. Most messaging apps accept PNG.
Best Format for Sharing with Non-Technical Users
When you do not know what software the recipient uses, prioritize universal compatibility over file size or quality:
For photos: JPEG. Every device, every app, every platform can open JPEG without issue.
For documents: PDF. Never send a Word document when the recipient just needs to read it — they may not have Word, or their version may display it differently.
For graphics and logos: PNG. More universally supported than WebP in desktop applications and older systems.
Avoid sending: WebP (poor application support outside browsers), HEIC (poor support on non-Apple devices), RAW formats (requires special software), TIFF (large files, limited application support outside design tools).
When in doubt, JPEG for images and PDF for documents will work for virtually every recipient in every context.
Quick Reference: Best Formats by Use Case
Photo attachments to email → JPEG (85–92% quality, resized to reasonable dimensions)
Photos on social media → JPEG (high quality for best platform compression results)
Logos and brand assets → SVG (if vector) or PNG (if raster)
Screenshots → PNG or WebP lossless
Documents, forms, contracts → PDF
Presentation decks to share as read-only → PDF
Graphics and illustrations → PNG or WebP lossless
Animations → Animated GIF (widest compatibility) or MP4 video
Phone photos to share with family → JPEG (compress if sending many)
Product images for e-commerce → WebP (web delivery) + JPEG (backup/download)
Files for printing → JPEG (300 DPI) or PDF
Files to archive long-term → PNG (photos and graphics, lossless), PDF/A (documents)
Frequently Asked Questions
What is the best image format to share online?
JPEG is the most universally compatible format for sharing photos online — every platform, app, and device accepts it. WebP is better for website delivery due to smaller file size, but JPEG is safer for sharing with arbitrary recipients.
Should I share photos as JPG or PNG?
For photographs: JPG. It is much smaller than PNG with imperceptible quality difference. For graphics, screenshots, and logos: PNG. The right choice depends on the content type, not a blanket rule.
What format should I use to share documents online?
PDF is the universal standard for document sharing. It preserves formatting across all devices and applications, is accepted everywhere, and prevents unintended editing.
Can I share WebP images on social media?
Most social media platforms do not accept WebP directly. Convert to JPEG before uploading to social media for best compatibility and results.
What format do iPhones use for photos?
iPhones save photos in HEIC format by default (since iOS 11). HEIC is not universally supported. For sharing with non-Apple users, convert HEIC to JPEG first using FileQuick's HEIC to JPG converter.