RSS Feed

Please wait while my feed loads

See more posts...


Subscribe to either one of our two newsletters for regular updates and information

Downloads newsletter

This is a weekly newsletter with download news, updates and other information

This is a monthly newsletter with software store information, offers and deals

OptiPNG 0.7.7

Compress PNG files without losing image quality

by Mike Williams

Our Rating:
Your Rating:
Login to rate
Based on 0 ratings
License: Open Source
Operating Systems: Windows 10, Windows 7 (32 bit), Windows 7 (64 bit), Windows 8, Windows Server, Windows Vista (32 bit), Windows Vista (64 bit), Windows XP
Languages: English
Software Cost: Free
Date Updated: 28 December 2017
Watchlist: Add download to my watchlist
Downloads To Date: 910
Developer: Cosmin Truta
RSS News Feed:
Buy Malwarebytes 3.0 Premium with a 1-PC license for only $29.99, saving 50% from
Compress PNG files without losing image quality

OptiPNG is a tiny command line tool which optimises PNG files, often reducing their size but without affecting image quality.

Our tests showed varying results. OptiPNG barely made any difference at all with some files, occasionally cutting others by 20% or more, but on average saved around 5%.

Using the program can be as simple as entering something like:

optipng image.png

OptiPNG then tries various parameters to find which delivers the smallest file size. But beware, if there are savings to be made then it overwrites the original file.

If you'd prefer to keep the source file, use:

optipng -keep image.png

It'll be preserved as image.png.bak.

Multiple images may be specified on the same command line:

optipng -keep image1.png image2.png image3.png

There are various other options to control the compression strategy, how and where any saved files are written. Enter optipng -h to find out more.

If you'd prefer a GUI, note that PNGGauntlet provides a shell for OptiPNG, and adds a couple of other tools to deliver even greater savings.

What's new?

 * Upgraded libpng to version 1.6.34.
 * Upgraded zlib to version 1.2.11-optipng.
 * Upgraded minitiff to version 0.2.
!! Fixed a buffer overflow vulnerability in the GIF decoder.
   [Reported by Joonun Jang]
!! Fixed an integer overflow vulnerability in the TIFF decoder.
   [Reported by Jaeseung Choi]
 ! Fixed the build on macOS High Sierra.
   [Reported by various users]
   [Fixed by Yuen Ho Wong and Friedrich Preuss]
 ! Fixed the build on DJGPP.
 * Disallowed out-of-bounds values in rangeset options.


A powerful PNG optimizer, easy to use (by command line standards) but with plenty of low-level control for experts.

Your Comments & Opinion
Related Download Articles
Caesium 1.7.0

Caesium 1.7.0

Open Source

An easy-to-use image compressor

Image Optimizer 1.0

Image Optimizer 1.0

Trial Software

Compress PNG images without losing quality

PNGGauntlet 3.1.2

PNGGauntlet 3.1.2


Reduce the size of PNG images without any loss in quality

PngOptimizer 2.4.1

PngOptimizer 2.4.1


Shrink PNG files without losing image quality


Riot 0.6


Reduce your website images to their smallest acceptable size with this very useful graphics tool

Other Download Articles From This Category
YouTube for iOS

YouTube for iOS 13.10


An unbundled iOS version of YouTube breathe new life into mobile video


CPix 1.6.1


View MPO, animated GIFs, TIFFs, more

Zortam MP3 Media Studio

Zortam MP3 Media Studio 23.45

Free, for personal-use only

View, organise, tag and generally get your MP3 collection in order with this powerful toolkit

jAlbum 15

jAlbum 15.3.2

Trial Software

Create stylish web albums from your favourite digital photos

From Softwarecrew

Please wait while my feed loads

See more posts...

Our Price: $19.95
RRP: $49.99
Saving 60%
Buy Now
Offer Ends In:

Spotlight: Free Full Software

WhatsApp Messenger 2.18.31

Free Full Commercial Software

WhatsApp Messenger is the world's most popular instant messaging app for smartphones.

You can use it to send and receive text and voice messages, photos, videos, even call your friends in other countries, and because it uses your phone's internet connection it might not cost you anything at all (depending on whether you'll pay data charges).

It's easy to set up and use. There's no need to create and remember new account names or pins because it works with your phone number, and uses your regular address book to find and connect you with friends who use WhatsApp already.

You can talk one-to-one or in group chats, and because you're always logged in there's no way to miss messages. Even if your phone is turned off, WhatsApp will save your messages and display them as soon as you're back online.

There's plenty more (location sharing, contact exchange, message broadcasting) and the app is free for a year, currently $0.99/ year afterwards.

What's New in Version 2.18.30

- Bug fixes