Batch Image Format Converter
Convert multiple images to JPG, PNG, or WebP in a ZIP file
Batch Image Format Converter — what it does
Convert a whole selection of images to JPG, PNG or WebP in one pass, with a quality control for the lossy formats, and collect the results as a ZIP. Each file is decoded and re-encoded locally through the canvas, so mixed input sets — a few PNGs, some HEIC-exported JPGs, a stray WebP — all come out in one consistent format.
When this tool helps
- Normalising an image folder before importing it into a system that only accepts one format.
- Moving a site's assets to WebP to cut page weight without touching layout or markup.
- Turning transparent PNG exports into flat JPGs for a printer or a document that cannot handle alpha.
How to use it
- Select the images to convert.
- Choose the output format.
- Set output quality for JPG or WebP.
- Download the converted set as a ZIP.
Accuracy, limits, and good practice
- Converting PNG to JPG discards transparency, and transparent areas are flattened — check logos and cut-outs before shipping them.
- Converting JPG to PNG makes files larger without restoring quality; the compression already applied cannot be undone.
- Formats the browser itself cannot decode, such as camera RAW or unconverted HEIC, will not open here.
Frequently asked questions
Does converting improve image quality?
No. Conversion can only preserve or reduce what is already in the file. Every lossy re-encode loses a little more detail.
Is WebP safe to use now?
Yes. Chrome, Edge, Firefox and Safari have all supported WebP for years, and it is a sensible default for photography on the web.
Are the original filenames kept?
Yes, with the new extension applied. Use the batch renamer first if you also want a different naming pattern.
Related tools on this site
- Batch Image Renamer — Rename image files with numbered patterns in a ZIP
- Image Collage Maker — Arrange multiple images into a downloadable grid
- Image Histogram — Inspect brightness and RGB distribution in an image
Everything above runs inside this page. Batch Image Format Converter needs no account, no upload, and no server round trip — close the tab and nothing is left behind.
批量圖片格式轉換能做什麼
一次把整批圖片轉成 JPG、PNG 或 WebP，有損格式還可調整品質，結果統一打包成 ZIP。每個檔案都在本機透過 canvas 解碼再編碼，因此混雜的來源——幾張 PNG、幾張由 HEIC 匯出的 JPG、偶爾一張 WebP——都能輸出成一致格式。
什麼時候用得上
- 匯入只接受單一格式的系統前，先把圖片資料夾統一格式。
- 將網站素材改為 WebP 以減少頁面重量，不必更動版面或程式碼。
- 把帶透明背景的 PNG 轉成平面 JPG，供不支援透明度的印刷或文件使用。
使用步驟
- 選擇要轉換的圖片。
- 選擇輸出格式。
- 為 JPG 或 WebP 設定輸出品質。
- 下載轉換完成的 ZIP 檔。
精確度、限制與實務建議
- PNG 轉 JPG 會失去透明度，透明區域將被填平，去背圖與商標請先確認再交付。
- JPG 轉 PNG 只會讓檔案變大，並不會還原畫質，已經壓掉的資料無法復原。
- 瀏覽器本身無法解碼的格式，例如相機 RAW 或未轉檔的 HEIC，在這裡無法開啟。
常見問題
轉檔會讓畫質變好嗎？
不會。轉檔只能保留或減少檔案中既有的資訊，每次有損重新編碼都會再損失一些細節。
現在可以放心用 WebP 嗎？
可以。Chrome、Edge、Firefox 與 Safari 支援 WebP 已有多年，網頁照片用它當預設格式相當合理。
會保留原本的檔名嗎？
會，只是換上新的副檔名。若也想改命名規則，可先用批量重新命名工具。
本站相關工具
以上步驟全部在這個頁面內完成，批量圖片格式轉換 不需要註冊、不上傳檔案、也不經過伺服器，關閉分頁後不會留下任何資料。