Why is TinyPNG slightly better at compression?

Their quantizer is a tuned, proprietary derivative of pngquant — years of optimization against a huge corpus. UPNG.js (what we use) is a solid open-source quantizer but ~3–5% behind on file size. For most workflows that's a fair trade for the privacy + unlimited usage.

Is the quality really 'identical'?

Identical is a marketing word. At 256 colors, the difference is invisible to nearly everyone — including most professional designers. At 64 colors you start to see banding on smooth gradients (sky, soft shadows). For UI screenshots and illustrations, 64 is fine. For photography with smooth gradients, stay at 256.

Can I batch compress?

Today, one at a time. Drop in a PNG, get the compressed PNG, repeat. A real batch UI is on the roadmap; for now, [Image Resize](/image-resize) and our other tools can be called repeatedly.

Does this affect SEO or page speed?

Yes, hugely. Smaller PNGs = faster page loads = better Core Web Vitals = better SEO. For images that are loaded above-the-fold on a public page, compress them aggressively before deploying.

Comparisonscomparison image tinypng png

Toolsly vs TinyPNG: PNG compression compared

May 19, 2026 · Toolsly

Both shrink PNGs to a fraction of the original. Here's how Toolsly's in-browser quantization stacks up against TinyPNG.

What both tools do

Both take a 24-bit PNG (millions of colors) and rebuild it as an 8-bit PNG (256-color palette). For photos and screenshots that's a 50–80% file-size cut with effectively no visible difference. TinyPNG popularized the technique 13 years ago; the underlying algorithm is well-understood.

The big difference is where the compression runs.

Side-by-side

	Toolsly PNG Compress	TinyPNG
Compression algorithm	UPNG.js (palette quantization)	Proprietary (pngquant-derived)
Where it runs	Your browser	TinyPNG servers
Files uploaded?	No	Yes
Daily free limit	Unlimited	20 images
Max file size	~50 MB practical	5 MB free, 75 MB paid
Account	None	None for free tier
Price	Free	Free up to 20/mo; $0.009/image after, or $39/yr unlimited
API	No (uses the same tool URL)	Yes, paid
Lossless mode	Yes (set palette to 256)	Yes (paid)
Visual quality	Very good at 256, good at 64	Slightly better at any setting

File-size results (rough)

We tested both tools on five typical inputs. Numbers are output / original.

Source	Toolsly (256 colors)	TinyPNG
iOS screenshot (1290×2796, UI)	32%	28%
Photo with sky (3000×2000)	42%	36%
Pixel art / icon (256×256)	17%	15%
Logo with text (800×400)	23%	21%
Chart screenshot (1920×1080)	28%	24%

TinyPNG wins by ~3–5 percentage points across the board. That's their better quantizer doing real work.

When Toolsly's compression is the right call

Sensitive screenshots. UI mocks, product designs, internal dashboards. Don't upload them.
Heavy daily usage. TinyPNG's free tier caps at 20 images/month. Toolsly has no limit.
Files > 5 MB. TinyPNG's free tier rejects them.
No-internet workflows. Once Toolsly's page is loaded, the compression keeps working even if you go offline.

When TinyPNG wins

Extracting the last 3–5% of compression matters (asset bundles for a public website).
You want their API integration for an automated pipeline.
You want their WebP / AVIF output features (we have those as separate tools).

How to use Toolsly PNG Compress

Go to /png-compress
Drop the PNG (or paste it from your clipboard with ⌘V / Ctrl+V)
Pick a palette size — 256 is the safe default, 64 is aggressive but still good for screenshots, 32 is for icons and pixel art only
Click Compress. The result shows inline so you can verify it looks right.
Download the compressed PNG.

For PNGs with lots of fine detail, stick with 256. For anything cartoon-like, illustrations, or screenshots with flat UI, drop to 128 or 64 and the difference is invisible.

What else Toolsly does that TinyPNG doesn't

Compress GIFs
Resize images
Convert to WebP / AVIF — newer formats often beat PNG-quantized for the same visual quality
Convert any image format to any other — 60+ image conversion tools

Give /png-compress a try with a real PNG and check the file sizes against your current workflow.

Frequently asked questions

Why is TinyPNG slightly better at compression?: Their quantizer is a tuned, proprietary derivative of pngquant — years of optimization against a huge corpus. UPNG.js (what we use) is a solid open-source quantizer but ~3–5% behind on file size. For most workflows that's a fair trade for the privacy + unlimited usage.
Is the quality really 'identical'?: Identical is a marketing word. At 256 colors, the difference is invisible to nearly everyone — including most professional designers. At 64 colors you start to see banding on smooth gradients (sky, soft shadows). For UI screenshots and illustrations, 64 is fine. For photography with smooth gradients, stay at 256.
Can I batch compress?: Today, one at a time. Drop in a PNG, get the compressed PNG, repeat. A real batch UI is on the roadmap; for now, [Image Resize](/image-resize) and our other tools can be called repeatedly.
Does this affect SEO or page speed?: Yes, hugely. Smaller PNGs = faster page loads = better Core Web Vitals = better SEO. For images that are loaded above-the-fold on a public page, compress them aggressively before deploying.