Practical image compression, without the guesswork.

New in-depth guides

Full step-by-step guides for specific size targets, exam forms and format choices.

• Compress Photo for Exam Forms — the exact photo and signature KB limits for SSC, UPSC, IBPS, NEET and Railways, in one table.
• Compress Image to 20KB — hit an exact 20KB target without guessing quality numbers.
• Compress Signature to 20KB — scan, crop and shrink signatures for SSC and bank exam forms.
• Compress Image to 50KB — passport photos and email attachments at exactly 50KB.
• Reduce Photo to 100KB — shrink ID photos privately, right in your browser.
• Compress Image to 200KB — the roomy target for web and document images.
• WebP vs JPG — real byte-size comparisons at matched quality, and when each format wins.
• Compress PNG Without Losing Quality — lossless optimization vs quantization, explained simply.
• Compress Images Without Uploading — why browser-local processing matters, and how to verify it yourself in the Network tab.
• TinyPNG Alternative — five free compressors compared honestly on limits, signup and privacy.
• Compress Image to 100KB— hit an exact 100KB target without guessing quality numbers
• Compress Signature for SSC, IBPS Exam Forms— scan and shrink signatures to exact exam-form limits

How to compress an image to 100KB

A 100KB limit is a concrete constraint, so start with the constraint rather than a generic quality number. In SizeMint, select the 100KB target and let the compressor search for a suitable encoding.

1. Look at the source dimensions

A modern phone can produce an image thousands of pixels wide. If the destination displays the image at a much smaller size, preserving every source pixel may be wasteful. Setting a sensible maximum width can make a larger quality setting possible while still meeting the byte limit.

2. Pick the format that matches the image

Photographs usually benefit from JPG or WebP. Screenshots, simple graphics and transparent artwork may need PNG. If the destination accepts WebP, it can be a useful option when the goal is a small photographic file.

3. Inspect important details

After compression, check faces, text, thin lines and high-contrast edges. A file can meet 100KB while looking worse than necessary if the dimensions or quality were pushed too far.

4. If 100KB is impossible, change the trade-off

Some images simply contain too much information for a very small target. Reduce dimensions, accept a slightly larger target, or use a more efficient output format when the destination permits it.

Quick guides for common file-size limits

Different upload systems use different limits, so the useful question is usually “what limit do I need to meet?” rather than “what quality should I use?” Start with the target in SizeMint, then inspect the real output.

20KB

A 20KB target is very restrictive for photographs. Expect to reduce dimensions substantially and accept visible quality trade-offs. Simple graphics may reach it more easily than detailed photos.

50KB

For a small profile photo or document thumbnail, 50KB can be workable when the display dimensions are modest. Resize before pushing quality extremely low.

200KB

200KB gives photographs more room to retain detail. Start with a sensible display width, then compare JPG and WebP outputs when the destination accepts both.

500KB

500KB is often a practical middle ground for larger web or document images. Check the image at its actual display size before reducing quality further.

1MB

A 1MB target is substantially less restrictive than 100KB. For many ordinary photos, preserving useful dimensions and using a modern lossy format may be enough to stay below the limit.

JPG vs WebP vs PNG: a practical choice

JPG is a dependable choice for photographs and remains widely supported. It is lossy, so strong compression can produce visible artifacts.

WebP is a modern web-oriented format with lossy and lossless modes. It often offers a useful balance for photographs and general web images.

PNG preserves image data losslessly and supports transparency. It is excellent for logos, diagrams, screenshots and graphics, but a photographic PNG can be much larger than a JPG or WebP.

When a destination explicitly requires one format, follow that requirement. Otherwise, compare the actual output at its intended display size rather than assuming one format is always best.

Why resizing can beat aggressive compression

File size is influenced by both the number of pixels and how those pixels are encoded. If an image is 6000 pixels wide but will be displayed at 900 pixels, keeping all 6000 pixels can make a small upload target unnecessarily difficult.

Reducing width first can preserve a cleaner-looking image than forcing a very low quality setting. The right maximum width depends on the destination: an avatar, a document thumbnail and a full-width website image have different needs.

How to reduce image size without making it look bad

• Start from the destination. Know the maximum bytes and approximate display dimensions.
• Resize when appropriate. Remove pixels that the destination cannot display meaningfully.
• Choose the format intentionally. Use JPG/WebP for many photographs and PNG where lossless data or transparency matters.
• Use moderate quality. Extreme quality reductions can create halos, blockiness and smeared textures.
• Check the result at real size. A zoomed-in artifact may be irrelevant—or a small artifact around text may be very noticeable.
• Keep the original. Treat compressed output as a derivative, not a replacement for your source.

Why some images refuse to reach a tiny target

There is no fixed “pixels = bytes” formula. A clean illustration with flat colors can compress very differently from a noisy photograph full of leaves, hair, grass or fine texture. Transparency can also affect how a format behaves.

Browser encoders have their own limits, too. A responsible tool should report when a target cannot be reached instead of claiming an exact size that it did not actually produce.

More image formats: what SizeMint can handle

SizeMint can import JPG/JPEG, PNG, WebP and AVIF, plus common GIF and BMP files when the browser can decode them. GIF input is treated as a still image, so animation is not preserved by the canvas-based compressor.

For output, SizeMint offers JPG, PNG and WebP, with AVIF exposed when the current browser can encode AVIF through its canvas APIs. This feature detection matters because browsers can fall back to PNG when a requested canvas output type is unsupported.

Preparing images for a website

For website images, think about the rendered size first. Serving a 4000-pixel image into a 700-pixel container creates unnecessary work for visitors. Exporting a suitably sized derivative can reduce transfer size while keeping the image sharp at its actual display dimensions.

Use modern formats when your publishing system and audience support them, and keep a fallback format when compatibility requires it. Compression should be paired with sensible dimensions rather than used as the only performance technique.

Compress Photo for Exam Forms: SSC, UPSC, IBPS Size Guide

Government exam portals reject photos that miss their exact size limits. This guide covers photo and signature limits for SSC, UPSC, IBPS and similar exams — and how to prepare a compliant image in your browser.

Compress Image to 20KB Online

Some upload forms ask for "under 20KB", not "80% quality". This guide shows how to hit an exact 20KB target in your browser: entering the target, inspecting the result honestly, and what to do when an image can't reach it.