Estimate File Sizes Instantly Before You Ship

4/25/2025·by xlocale Team

#developer-tools#performance#gzip#brotli#xlocale

🥇 What is Gzip?

Gzip is a file compression algorithm that’s been around since the 90s — and it’s still the default compression method for most web servers.

📦 Compresses text-based files (HTML, CSS, JS)
🔧 Supported by every browser
🔄 Faster to compress, not always the smallest

Think of Gzip as the "safe choice" — battle-tested, reliable, and widely adopted.

🚀 What is Brotli?

Brotli is a newer, smarter compression algorithm created by Google.

🧠 Uses dictionary + context modeling = better compression
🐢 Slower to compress, but much smaller file sizes
⚡ Supported by all major browsers

Think of Brotli as the "next-gen" optimizer — especially for static content.

🧪 Use Case Scenarios

Use Case	Use Gzip	Use Brotli
Dynamic content (APIs, server-rendered pages)	✅ Faster to compress	❌ Not ideal
Static assets (HTML, CSS, JS, fonts)	✅ OK	✅✅ Best choice
First load performance critical (e.g. landing pages)	👍	🚀 Definitely
Older browsers / max compatibility	✅ Always works	✅ Mostly works

📦 File Size Estimator — Know Before You Ship

Ever deployed a website, only to get a Lighthouse slap for sending bloated assets across the wire?

Yeah. Same.

That’s why we built the File Size Estimator — a no-friction tool to:

✅ Estimate raw, gzip, and Brotli sizes
✅ Compare text, JSON, images, and base64 blobs
✅ Paste, upload, or drag-and-drop — your choice
✅ Understand the real network cost before it hits production

🚀 Why it Matters

Modern users expect fast. But fast doesn’t just mean good code — it means:

Small payloads
Efficient compression
Realistic expectations on mobile & slow networks

If you’re shipping:

JSON APIs
Web bundles
Image-heavy UIs
Base64 inline content

You should know what the compressed version actually looks like.

Because that’s what browsers load.

Try it! 🔥

Option 1: Upload File

Drag & drop a file or

Option 2: Paste Text

Enter JSON, Base64, or any text data.

Size Estimates

Original and estimated compressed sizes from original image.

Original Size

Gzip Estimate

Brotli Estimate

🧪 Example

Let’s say you're bundling a payload of:

{
  "users": [{ "id": "abc123", "name": "John" }, ...]
}

It looks small in your editor... But is it 5KB or 50KB over the wire? Drop it into xlocale.com/tools/file-size-estimator — and you’ll see:

Raw: 42.1 KB
Gzip: 12.3 KB
Brotli: 10.7 KB

Now you actually know what your users are downloading.

💡 Use Cases :

Validate the size of config files before shipping them via CDN
See the true weight of large JSON files served from your API
Check how well your site images compress under Brotli
Estimate if your base64 logo is bloating your CSS

🛠 Built for Devs, Not Sales Teams No login. No limits. Just a clean utility that does one thing right.

Keep it small. Keep it fast. Keep building.
🔥 xlocale team

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