Does isCompress upload my images?

No. isCompress processes images entirely in your browser locally. No images are ever uploaded to any server. Your image data stays on your device, ensuring complete privacy.

What image formats does isCompress support?

isCompress supports uploading JPG/JPEG, PNG, WebP, GIF, and BMP images. You can choose to output compressed images in JPEG, PNG, or WebP format.

Is there a file size limit for image compression?

Single images up to 20MB are supported. You can batch upload multiple images for simultaneous compression and download them all as a ZIP file.

Is isCompress completely free to use?

Yes, isCompress is 100% free with no registration required and no usage limits. Simply open the page and start compressing your images instantly.

How do I compress a screenshot using Ctrl+V paste?

Take a screenshot using PrintScreen (Windows) or Cmd+Shift+4 (macOS), then navigate to isCompress and press Ctrl+V. The screenshot is automatically pasted and compression begins immediately.

How does isCompress compare to TinyPNG or Squoosh?

Unlike TinyPNG, isCompress processes images entirely in your browser — no uploads, no server processing, and no API limits. Compared to Squoosh, isCompress adds batch compression, ZIP packaging, and clipboard paste support.

Can I compress multiple images at once?

Yes! isCompress supports batch compression. Fast mode processes multiple images concurrently, while Deep mode uses a safer low-concurrency path for heavier WASM compression. Download all results as a single ZIP file.

isCompress 会上传我的图片吗？安全吗？

不会。isCompress 所有处理100%在浏览器本地完成，不上传服务器，极致保护您的隐私。您的图片数据始终留在本地设备上。

isCompress 支持哪些图片格式？

支持上传 JPG/JPEG、PNG、WebP、GIF、BMP 格式的图片。可以将压缩结果输出为 JPEG、PNG 或 WebP 格式。

isCompress 是免费的吗？有使用限制吗？

极速、安全、完全免费。无需注册，无使用次数限制，打开网页即可使用。所有处理都在本地完成，不消耗服务器资源。

如何批量压缩图片并打包下载？

选择多张图片上传，isCompress 会以 3 路并发自动压缩所有图片。完成后点击「打包下载 ZIP」按钮即可一键下载所有压缩后的图片。

isCompress 和 TinyPNG 有什么区别？

与 TinyPNG 不同，isCompress 100%在浏览器本地处理，不上传图片到服务器，没有 API 限制。同时支持批量压缩、ZIP 打包、剪贴板粘贴等功能。

压缩图片会降低画质吗？

isCompress 提供可调节的压缩质量滑块，让您在文件大小和画质之间自由平衡。实时预览功能让您在下载前对比原图和压缩后的效果。

Lädt isCompress meine Bilder hoch?

Nein. isCompress verarbeitet Bilder vollständig lokal in Ihrem Browser. Es werden niemals Bilder auf einen Server hochgeladen. Ihre Bilddaten verbleiben auf Ihrem Gerät.

Welche Bildformate werden unterstützt?

Unterstützt werden JPG/JPEG, PNG, WebP, GIF und BMP zum Hochladen. Die komprimierte Ausgabe kann im JPEG-, PNG- oder WebP-Format erfolgen.

Ist isCompress kostenlos?

Ja, isCompress ist völlig kostenlos. Keine Registrierung erforderlich, keine Nutzungsbeschränkungen. Einfach die Seite öffnen und mit dem Komprimieren beginnen.

Kann ich mehrere Bilder gleichzeitig komprimieren?

Ja! isCompress unterstützt Stapelkomprimierung mit 3 parallelen Verarbeitungsprozessen. Wählen Sie mehrere Bilder aus und laden Sie alle Ergebnisse als einzelne ZIP-Datei herunter.

isCompress télécharge-t-il mes images ?

Non. isCompress traite les images entièrement dans votre navigateur localement. Aucune image n'est jamais téléchargée sur un serveur. Vos données d'image restent sur votre appareil.

Quels formats d'image sont pris en charge ?

Les formats JPG/JPEG, PNG, WebP, GIF et BMP sont pris en charge. La sortie compressée peut être au format JPEG, PNG ou WebP.

isCompress est-il gratuit ?

Oui, isCompress est entièrement gratuit. Aucune inscription requise, aucune limite d'utilisation. Ouvrez simplement la page et commencez à compresser.

Puis-je compresser plusieurs images à la fois ?

Oui ! isCompress prend en charge la compression par lots avec 3 processus parallèles. Sélectionnez plusieurs images et téléchargez tous les résultats dans un seul fichier ZIP.

¿isCompress sube mis imágenes?

No. isCompress procesa las imágenes completamente en tu navegador de forma local. Nunca se sube ninguna imagen a un servidor. Tus datos de imagen permanecen en tu dispositivo.

¿Qué formatos de imagen son compatibles?

Se admiten JPG/JPEG, PNG, WebP, GIF y BMP para la carga. La salida comprimida puede estar en formato JPEG, PNG o WebP.

¿isCompress es gratuito?

Sí, isCompress es completamente gratuito. No requiere registro ni tiene límites de uso. Solo abre la página y comienza a comprimir.

¿Puedo comprimir varias imágenes a la vez?

¡Sí! isCompress admite compresión por lotes con 3 procesos paralelos. Selecciona varias imágenes y descarga todos los resultados en un solo archivo ZIP.

Privacy-First Image Compressor · Fast & Deep Modes

isCompress compresses images entirely in your browser with zero uploads. Choose Fast mode for instant Canvas compression or Deep mode for stronger WASM compression on JPEG, PNG, and WebP, with batch ZIP download.

What is isCompress?

isCompress is a free online image compression tool that processes images entirely in your browser. Unlike traditional compression services, isCompress never uploads your images to any server. All processing happens locally on your device, ensuring 100% privacy and security.

Key Features

Privacy Safe — Images are processed locally in the browser, never sent to any server. Zero data leakage.
Fast & Deep Modes — Use instant Canvas compression for speed or WASM deep compression for smaller JPEG, PNG, and WebP files.
Batch Compression & ZIP Download — Upload and compress multiple images at once, download as a single ZIP file.
Format Conversion — Convert between JPEG, PNG, and WebP formats during compression.
Clipboard Paste — Press Ctrl+V to paste and compress screenshots directly, no need to save files first.
Supports JPG, PNG, WebP, GIF, BMP — Wide upload support with deep mode available for JPEG, PNG, and WebP.

How to Compress Images

Open iscompress.com in any modern browser
Click the upload area or drag and drop your images
Choose Fast or Deep mode, then adjust output format and compression quality
Download compressed images individually or as a ZIP package

Frequently Asked Questions

Does isCompress upload my images?: No. isCompress processes images entirely in your browser locally. No images are ever uploaded to any server.
What image formats are supported?: Supports JPG/JPEG, PNG, WebP, GIF, and BMP uploads. Output can be JPEG, PNG, or WebP.
Is isCompress free?: Yes, completely free. No registration required, no usage limits.
Can I compress multiple images at once?: Yes! Fast mode processes images concurrently, while Deep mode uses safer low-concurrency WASM compression. Download all results as ZIP.

isCompress - 免费在线图片压缩工具

isCompress 是一款免费的在线图片压缩工具，完全在浏览器本地处理图片，不上传至任何服务器，确保隐私安全。支持快速 Canvas 模式和 WASM 深度模式，可批量压缩、格式转换并一键打包 ZIP 下载。

本工具需要 JavaScript 运行，请在浏览器设置中启用 JavaScript 后刷新页面。

JavaScript is required to use the compression tool. Please enable JavaScript in your browser settings and refresh the page.