What is MiniPx?
MiniPx is a free image compressor, converter and resizer that runs entirely inside your web browser. It is built and maintained by Gaurav Bhowmick and lives at minipx.com. Unlike TinyPNG, FreeConvert or Cloudinary, compressing, converting and resizing have no upload step and no server-side processing: images are decoded, re-encoded and written back to disk by JavaScript, WebAssembly codecs and the Canvas API running on your own device. For that work there is no account, no daily or monthly quota, and nothing to delete afterwards, because nothing was ever sent anywhere. The one server-side path on the site is Cloud HD, a Pro-only option on 7 AI tools, described in the Pro section below.
Everything on this page is free. MiniPx Pro costs $3.24 for the first month or $29 for the first year on the launch promo until Nov 30, 2026 ($4.99/month and $39/year after), and it lifts the free tier's five-files-per-batch cap, adds responsive image sets, multi-format export, watermarking, saved presets and 6 batch rename templates, and raises the AI background remover from 1080px watermarked output to 4096px without a watermark. Per-file input is capped at 200 MB; beyond that the constraint is your device's memory rather than our infrastructure, since there is none.
Compression
MiniPx compresses JPEG, PNG, WebP, AVIF and GIF images (an animated GIF is flattened to its first frame). PDFs are not compressed directly: the PDF tool renders pages to images and rebuilds a PDF from images, which shrinks scans at the cost of selectable text. Compression runs client-side using WebAssembly codecs, the Canvas API and Web Workers — your images never leave your browser tab. Three preset levels (Gentle, Smart, Tiny) cover every use case from portfolio-quality to minimum file size. Auto Quality analyses each image individually and picks the optimal setting.
Target-size compression lets you hit exact file size limits: 5KB through 2MB. This handles government form uploads (50KB for Indian exam portals), social media limits, and email attachment constraints without trial and error.
Format conversion
Convert between 9 image formats: JPEG, PNG, WebP, AVIF, BMP, TIFF, SVG, GIF, and HEIC. Common conversions include PNG to JPG (reduce file size), HEIC to JPG (iPhone compatibility), WebP to PNG (editing compatibility), and JPG to AVIF (next-gen compression).
Every conversion strips EXIF metadata automatically. SVG to raster conversion (PNG or JPG) renders vectors at full resolution. HEIC decoding uses the libheif WebAssembly decoder so iPhone photos work on any browser without installing additional software.
Resize, crop, and rotate
Resize images by pixel dimensions or target file size. Crop to specific aspect ratios. Rotate to fix orientation. Dedicated presets for passport photos (various country specifications), social media platforms (Instagram, Facebook, LinkedIn, YouTube, Twitter), and common web dimensions.
The resize-in-KB tool combines dimension scaling with compression to hit a specific file size target — useful when a platform requires both dimension and size constraints simultaneously.
Platform-specific optimization
Pre-configured compression settings for 12 platform targets: Instagram (post, story, reel cover), LinkedIn (post, profile picture), X (post, header), Facebook, YouTube thumbnails, WhatsApp status, email attachments, and resume photos. Each preset applies the correct dimensions, format, and file size for that platform.
Bulk processing
Drop multiple files at once. Each image processes independently in parallel using Web Workers. Download results individually or as a single ZIP archive. Free tier processes 5 files per batch; Pro removes the cap entirely.
Pro tier ($3.24 first month, $29 first year)
Pro keeps everything on your device by default — Cloud HD, below, is the one opt-in exception — and adds production-grade controls for people who ship images every day. One input becomes a complete responsive set (150 / 640 / 1280 / 2560 px), exported across AVIF, WebP, JPG, and PNG simultaneously — up to 16 outputs per input via Cartesian product.
Watermarking applies to both the primary output and every responsive variant, with 9 anchor positions, opacity and scale controls — see the bulk watermark workflow. Twelve platform presets cover Instagram, LinkedIn, X, Facebook, YouTube, WhatsApp, and Resume Photo specs in one click. Saved presets bundle your favourite combination of size, format, watermark, codec and rename template for one-click application later.
Advanced codec controls expose JPEG chroma subsampling and per-format quality overrides, which apply to every output in that format, primary included — leave one blank and that format follows the main quality setting. Batch rename offers 6 fixed naming templates — sequence, date, width, format, or keep the original name — so output filenames stay tidy across batches. A free preview lets you try the full Pro stack on one compression per browser, no signup required. Persona pages: for SEO + Core Web Vitals, for ecommerce, for developers.
Pro AI tools unlock 4K background removal (vs 1080p free) and passport photos from a higher-resolution source pipeline, with a manual crop and a 4×6 inch print sheet. The delivered passport photo is sized to the country’s official spec on either tier. Use cases include LinkedIn headshots, product photos, logos, and full background replacement. License activation is server-validated through Paddle, then HMAC-signed so a forged localStorage entry cannot unlock Pro features. Activations are capped at 5 browsers on both the monthly and annual plans, with self-service device management at /account/.
Cloud HD is the one part of MiniPx that runs on a server, and it is Pro-only. It puts a heavier model than a browser can hold behind 7 AI tools. On three it is a switch you turn on per run — the background remover, the image upscaler (with image enlarger and upscale to 4K) and the passport photo maker — and they run on your device until you do. The other 4 have no on-device mode at all: restore old photos, colorize a photo, AI photo enhancer and remove an object from a photo. Pro Monthly includes 150 cloud runs a month and Pro Annual 200, each including 10 HD runs; the allowance resets monthly, does not roll over, and a run that fails on our side is not charged. A Cloud HD photo is uploaded for that one run, processed in the United States, deleted when the run finishes, and in all cases within 24 hours, and never used to train anything.
PDF tools
Create PDFs from images (single or multi-page) using jsPDF. Extract PDF pages as images using pdfjs-dist. Compress existing PDFs by re-rendering pages at lower quality. All PDF processing runs locally — no upload to external services.
Privacy and security
Compression, conversion, resizing and the PDF tools run in JavaScript inside your browser tab. Those files never enter a network request. They work offline after initial page load. EXIF metadata (GPS, camera info, timestamps) is stripped automatically. For that work MiniPx satisfies GDPR and the UK Data Protection Act by architecture rather than by policy, and it is safe for passport photos, medical images, legal documents and unreleased business materials. Cloud HD is the deliberate exception: it is Pro-only, off until you switch it on, processed in the United States under standard contractual clauses, and the photo is deleted when the run finishes, and in all cases within 24 hours. The detail is in section 2A of the privacy policy.
Supported formats
| Format | Compress | Convert from | Convert to |
|---|---|---|---|
| JPEG | ✓ | ✓ | ✓ |
| PNG | ✓ | ✓ | ✓ |
| WebP | ✓ | ✓ | ✓ |
| AVIF | ✓ | ✓ | ✓ |
| GIF | ✓ | ✓ | ✓ |
| HEIC | — | ✓ | — |
| BMP | — | ✓ | — |
| TIFF | — | ✓ | — |
| SVG | — | ✓ | — |
Technical details
MiniPx uses the browser's native Canvas API for JPEG and PNG encoding. WebP and AVIF go through WebAssembly encoders we ship, because Safari's Canvas API silently substitutes PNG when asked for WebP, and Chrome, Firefox, and Edge cannot write AVIF at all — only Safari 16+ encodes AVIF natively. HEIC decoding uses the libheif WebAssembly decoder. PDF creation uses jsPDF. PDF page extraction uses pdfjs-dist. Bulk processing uses Web Workers for parallel execution. No external image processing API is called for compression, conversion or resizing.
The entire application is a static site built with Next.js 16, exported as HTML/CSS/JS, and hosted on Netlify. There is no backend server in the path of a file you compress, and no file storage. The compression logic is the same whether you are online or offline. The server-side pieces are the ones you would expect from the billing side of a product — sign-in by emailed code, licence checks, and the Cloud HD queue — and none of them touches a file you compress, convert or resize.