Privacy-focused
image compression

BlockSurvey's free image compression is a privacy-focused tool. Simply upload your image
and image compression tool will work out the magic for you.

or drag and drop an image

It works for JPG, JPEG and PNG formats

Know how the privacy-focused
image compression works

Space is finite, our imagination is infinite. So we've built the best privacy-focused image compression tool out there in which the compression happens at the browser/client side itself and not in any server i.e. your images doesn't leave your machines. We apply the same rule to text: our browser-based encryption and decryption tool does its work on your machine too, so the plain text never reaches us.

Step 1 : Upload image files

Upload the image files you would like to compress.

Step 2 : Process files using browser image compression

The uploaded images are fed to the browser-image-compression module which processes them and returns the compressed images.

Step 3 : Download Compressed Images

Download the compressed images. You can also clear the list and go for fresh set of uploads.

Private by design: nothing leaves your browser

The photos people compress here are often the ones they care most about keeping private: ID scans, medical images, internal screenshots, personal photos. Uploading those to a random compressor's server just to shrink a file size hands them over for no good reason. This tool was built so that cannot happen:

100% client-side

Compression runs through the browser-image-compression library, which draws your image onto an HTML <canvas> on your device and reads the scaled-down data back from it. No image bytes are ever uploaded anywhere, which you can confirm for yourself in your browser's network tab.

Nothing stored or logged

There is no account and no history. Your images live only in the page's memory and are gone the moment you close the tab or reload the page.

Works offline

Once the compression library has finished loading, you can disconnect from the internet and keep compressing images. If a server were doing the work, it would stop the moment you went offline.

Built for developers and security-conscious teams

Anyone who needs a smaller image without handing it to a third-party server. BlockSurvey takes the same position on survey data with zero-knowledge surveys, where responses are encrypted before they ever reach a server.

Sensitive uploads

ID scans, medical images, and internal screenshots that need a smaller file size without touching a third-party server along the way.

Developers

Shrink images for a site or app before upload, without wiring up a server-side compression step or an API with a rate limit.

Everyday sharing

Privacy-conscious users compressing personal photos before sending them over email or messaging apps that choke on large files.

Building something that handles sensitive data?

BlockSurvey runs on zero-knowledge surveys, so the responses you collect are never sold or mined. Responses are encrypted on the respondent's device, so the server stores nothing readable.

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Generate a strong random password, passphrase, or PIN in your browser with the Web Crypto API.

Encryption key generator

Generate AES-128, AES-192, and AES-256 keys or random secrets, entirely in your browser.

Encryption and decryption tool

Encrypt or decrypt text with AES-256-GCM. The message and passphrase never leave your browser.

Password strength checker

Check a password's real strength and entropy in bits, scored on your device and never sent anywhere.

PGP encryption tool

Encrypt, decrypt, and generate PGP keys. Keys and messages never leave your browser.

Hash generator

Generate MD5, SHA-256, HMAC, and bcrypt hashes, computed entirely on your device.

UUID generator

Generate UUID v4, v7, v1, or a GUID, one or a thousand at a time, entirely in your browser.

JWT decoder

Decode a JSON Web Token and verify its signature in your browser. The token and key never leave your device.

TOTP generator

Generate a live 6-digit 2FA code from a base32 secret, or create a secret to scan into your authenticator app.

CSP generator

Build a Content-Security-Policy header, then check an existing one for unsafe-inline and wildcards.

Base64 encoder and decoder

Encode text to Base64 and decode it back to text or a file, with URL-safe and MIME options.

URL encoder and decoder

Percent-encode and decode URLs, and split any URL into its decoded query parameters.

Hex converter

Convert between text, hex, binary, decimal, ASCII, and Base64 in any direction, with a live byte table.

PII redactor

Redact emails, phone numbers, credit cards, SSNs, IBANs, IPs, and API keys from text you paste or drop in.

Answer a short form and get a GDPR and CCPA privacy policy as HTML, Word, or PDF.

Terms and conditions generator

Draft terms for a website, app, store, or SaaS and download them as HTML, Word, or PDF.

Cookie policy generator

Build a cookie policy with a real cookie table covering name, provider, purpose, type, and duration.

Disclaimer and EULA generator

Pick the clauses you need, from affiliate disclosure to warranty and liability, and export the document.

Secure QR code generator

Generate a QR code entirely in your browser. The link goes straight to your destination, not through a tracking redirect.

Email bounce checker

Check a list of email addresses for bounces and bring your bounce rate down before you send.

These tools run in your browser because that is how we build everything. The same idea, applied to research: privacy-first surveys with end-to-end encryption.

Frequently asked questions

What is Image Compression?

Image compression is a process for optimizing images by encoding or converting a graphics file in a way that it will consume less storage space than the original one. It is a type of technique to compress image, using an image compressor tool without influencing or degrading the image quality to a greater extent.

What is the need for Image Compression?

Image Compression helps in website optimization i.e. reducing the time taken to load a website,it helps in cases where while uploading image, file size is restricted by certain types of servers, and finally it helps in reducing the storage impact on your hard drive.

Is it safe to use a free image compression tool?

All compression takes place in the browser itself and no data is taken to our servers for any kind of processing. The same holds for our QR code generator that builds the code entirely in your browser.

How many images can I compress at a time?

We allow multiple images to be uploaded and compressed in a single go.

Is this image compression tool a honey pot?

Here at BlockSurvey, we give at most importance to privacy which is consistent with our vision of a world having a decentralized internet space. As already mentioned above, the tool does not collect and store any form of data given to it. It simply acts as a platform for people to enter their images and get them compressed.

Why is it free?

The product is built from already existing open source code with slight tweaks by us. It was primarily built for compressing images in our own product i.e. BlockSurvey and at a certain point we had this idea of sharing the benefits accruing from this project with the rest of the world.

What are the modules used to build this?

The tool uses a npm module called browser-image-compression

How does image compression tool work?

The tool reads the data from the HTML file reader API and uses the browser-image-compression module to process it. The browser-image-compression module creates an HTML canvas element and draws the image on it and gets the scaled down data back from the canvas. The returned dataURI is read, decoded from Base64 and displayed to the user.

How is this different from a paid image compression tool?

The compression itself is the same category of work either way: lossy re-encoding to shrink file size. The difference is where that work happens. Most free and paid compressors, including TinyPNG-style tools, upload your image to their server, compress it there, and send back the result. That is fine for a random image you found online, but it is not something you want to do with an ID scan, a medical image, or an internal screenshot. This tool runs the same kind of compression (the browser-image-compression library, drawing on an HTML canvas) entirely in your browser, so the file never leaves your device. There is also no account, no per-image limit, and no monthly cap.

Does compression strip EXIF metadata from my photos?

In most cases, yes, though that is a side effect of how the tool works rather than a dedicated feature. Because compression happens by drawing the image onto an HTML canvas and reading the pixel data back (see how it works above), metadata blocks such as camera model, GPS coordinates, and timestamps embedded in the original file typically do not carry over to the compressed output. If you need a guarantee that a specific photo has no location data attached before you share it, check the downloaded file with an EXIF viewer rather than relying on this as a dedicated stripping tool.

Know how the privacy-focused image compression works