如果您的文档是PDF格式，那么它很可能是最终格式——准备好让您的观众惊叹不已。这是使用最高质量图形的地方，也是展示文本最终版本的地方，可以打印或与他人分享以阅读或分发。这可能意味着文件很大，尤其是在图像较多的文档中。
虽然您可以编辑 PDF(edit a PDF)，但您必须降低质量以减小整体文件大小。如果您想知道如何压缩PDF ，您可以通过压缩文件而不是使用(PDF)Windows和Mac上的内置或第三方软件或使用在线压缩服务来解决此问题。
如何在 Windows 上使用 PDF 压缩器压缩 PDF(How To Compress A PDF On Windows Using PDF Compressor)
在Windows 10上没有压缩(Windows 10)PDF的内置方法，除非您想先将其添加到 zip 文件(add it to a zip file)中。这意味着您需要使用第三方压缩工具来压缩PDF文件。
虽然确实存在多种工具，但最好的选择之一是Free PDF Compressor。这个免费的应用程序已经存在了好几年，但它仍然是在Windows上压缩(Windows)PDF的最简单、最快捷的方法之一。
- 下载(Download)、安装和运行Free PDF Compressor软件开始。在“免费 PDF 压缩器(Free PDF Compressor)”窗口中，单击“ PDF 文件(PDF File )”选项旁边的“浏览(Browse)”按钮以选择您的文件。在输出文件(Output File )框中提供压缩文件的位置和文件名。
- 在设置(Settings)部分下，您可以设置PDF文件的首选质量。屏幕(Screen)是最低质量的，而打印机(Printer )和印前(Prepress)是更高质量的选项。选择您希望使用的质量级别，然后按压缩(Compress)开始 PDF 压缩。
- 免费PDF 压缩器(PDF Compressor)会在文件压缩完成时提醒您。按确定(OK)关闭。
由于免费 PDF 压缩器(Free PDF Compressor)将压缩文件另存为原始文件，因此如果您对文件的结果不满意，可以以更高的质量重复该过程。
如何在 Mac 上使用预览压缩 PDF(How To Compress A PDF On Mac Using Preview)
与Windows不同，macOS 包含一个内置的PDF压缩功能，作为预览(Preview)应用程序的一部分，用于查看图像和文档。此应用程序包含在所有Mac 上(Macs)，您可以在Launchpad应用程序列表中找到它。
- 要在Mac(Mac)上压缩PDF文件，请打开“预览(Preview)”应用并选择要打开的PDF文件。打开后，从菜单栏中按File > Export
- 在“导出(Export )”选项菜单中，选择一个新文件名（或保留现有文件名以覆盖现有文件）和保存文件的位置。从Quartz Filter下拉菜单中，选择Reduce File Size选项。准备好开始压缩过程后，按保存。(Save)
预览(Preview)将立即保存您的PDF文档的更新、压缩版本。之后您需要在“预览(Preview)”中打开它，以预览应用对质量所做的（如果有的话）显着变化。
使用在线 PDF 压缩服务(Using Online PDF Compression Services)
如果您不想下载额外的软件来压缩您的PDF文件，您可以使用各种在线PDF压缩服务来代替。但是，如果您想使用这样的在线服务，您应该只使用非敏感文档。
使用这些服务涉及将文件上传到远程服务器，文件可以在其中保留一段时间。这会对任何可能包含个人数据的文档构成严重的安全风险，您应该只使用在线压缩站点来存储您愿意公开共享的文件。
存在各种在线压缩PDF文件的服务，例如I Love PDF。大多数服务以类似的方式工作，但是允许您上传文件、选择质量，然后下载压缩文件。
- 要使用 I Love PDF，请按选择 PDF 文件(Select PDF Files)按钮选择要压缩的PDF文件。(PDF)您还可以将文件直接拖放到网站窗口中以自动上传它们。
- 上传文件后，您可以从右侧菜单中选择压缩级别。压缩率越高，输出文件的质量越低（反之亦然）。选择极限压缩(Extreme Compression)以获得最大可能的压缩，选择推荐压缩(Recommended Compression)以获得中等压缩但具有合理的质量，或选择较少压缩(Less Compression )以获得最低压缩但获得更高质量。准备好后，按压缩 PDF(Compress PDF )按钮开始压缩。
- PDF压缩过程将在远程服务器上完成。完成后，按下载压缩的 PDF(Download Compressed PDF )按钮下载压缩文件。压缩量（节省的文件空间量）将显示在下方。
- 如果您想将文件保存到云存储，或使用 I Love PDF(Love PDF)服务分发给其他人，您可以使用下载按钮右侧的共享图标。其中包括共享到Google Drive或Dropbox的选项，以及创建二维码或共享链接以分发给他人。
- I Love PDF还提供删除选项，允许您从其服务器中删除文件。但是，要删除文件，请按Delete图标。虽然这将禁用 I Love PDF网站上的删除链接，但这并不能保证使用此方法将文件从网站服务器中完全删除。
如前所述，您不应将 I Love PDF之类的服务用于敏感文档。对于包含个人数据的任何类型的敏感文档，您应该使用软件选项来压缩文件，例如上面演示的Preview或Free PDF Compressor应用程序。(Free PDF Compressor)
共享和查看压缩的 PDF 文件(Sharing And Viewing Compressed PDF Files)
压缩PDF可让您减小文件大小，而不会过多降低质量（除非您愿意）。这样可以更轻松地通过电子邮件或其他文件共享服务(file sharing services)进行在线共享。您甚至可以使用密码保护您的 PDF 文件(password protect your PDF files)，以保护敏感文档的内容免受窥探。
如果您在打开PDF时遇到困难，则需要安装一个好的 PDF 阅读器(good PDF reader)，例如Adobe Acrobat或Foxit Reader。如果您想要在线选项，您可以将 PDF 转换为 Google Docs(convert PDFs to Google Docs)，让您可以从 Web 浏览器查看、编辑和共享文件，而无需先安装第三方应用程序。
How To Compress a PDF on Windows & Mac
If your document is in PDF formаt, it’s likely to be in its final format—ready to wow your audience. This іs where your highest quality graphіcs are used аnd where the final version of your text is presented, ready to рrint or share with others to rеad or distribute. This can mean large file sizeѕ, especially іf it’s an image-heavy document.
While you can edit a PDF, you’ll have to reduce the quality to reduce the overall file size. If you want to know how to compress a PDF, you can get around this issue by compressing the file instead using built-in or third-party software on Windows and Mac or by using an online compression service.
How To Compress A PDF On Windows Using PDF Compressor
There are no built-in methods to compress a PDF on Windows 10, unless you want to add it to a zip file first. This means you’ll need to use a third-party compression tool to compress the PDF file.
While several tools do exist, one of the best options is Free PDF Compressor. This free app has existed for several years, but it’s still one of the easiest and quickest ways to compress a PDF on Windows.
- Download, install, and run the Free PDF Compressor software to begin. In the Free PDF Compressor window, click the Browse button next to the PDF File option to select your file. Provide a location and file name for the compressed file in the Output File box.
- Under the Settings section, you can set the preferred quality of your PDF file. Screen is the lowest quality, while Printer and Prepress are higher quality options. Select the quality level you wish to use, then press Compress to begin the PDF compression.
- Free PDF Compressor will alert you when the file compression is complete. Press OK to close.
As the Free PDF Compressor saves the compressed file as a separate file to the original, you can repeat the process with a higher quality if you’re unhappy with how the file turns out.
How To Compress A PDF On Mac Using Preview
Unlike Windows, macOS includes a built-in PDF compression feature as part of the Preview app for image and document viewing. This app is included on all Macs, and you can find it in your Launchpad app list.
- To compress a PDF file on a Mac, open the Preview app and select a PDF file to open. Once opened, press File > Export from the menu bar.
- In the Export option menu, select a new file name (or leave the existing file name to overwrite the existing file) and the location to save the file. From the Quartz Filter drop-down menu, select the Reduce File Size option. Press Save once you’re ready to begin the compression process.
Preview will immediately save an updated, compressed version of your PDF document. You’ll need to open this in Preview afterwards to preview what (if any) noticeable changes in the quality have been made by the app.
Using Online PDF Compression Services
If you don’t want to download additional software to compress your PDF file, you can use various online PDF compression services instead. If you want to use an online service like this, however, you should only do so with non-sensitive documents.
Using these services involves uploading the file to a remote server, where the file could remain in place for a period of time. This poses a serious security risk for any documents that may contain personal data, and you should only use online compression sites for files that you would be happy to share publicly.
Various services exist to compress PDF files online, such as I Love PDF. Most services work in a similar way, however, by allowing you to upload the file, select the quality, and download the compressed file afterwards.
- To use I Love PDF, press the Select PDF Files button to select the PDF files you wish to compress. You can also drag and drop the files directly into the website window to upload them automatically.
- Once the files are uploaded, you can select the compression level from the right-hand menu. The higher the compression, the lower the quality of your output file (and vice versa). Select Extreme Compression for the maximum possible compression, Recommended Compression for medium compression but with reasonable quality, or Less Compression for the lowest compression but for much higher quality. Press the Compress PDF button to begin the compression once you’re ready.
- The PDF compression process will complete on the remote server. Press the Download Compressed PDF button to download the compressed file once it’s done. The compression amount (with the amount of file space saved) will be shown underneath.
- If you want to save the file to cloud storage, or distribute it to others using the I Love PDF service, you can use the sharing icons to the right of the download button. These include options to share to Google Drive or Dropbox, as well as to create a QR code or sharing link to distribute to others.
- I Love PDF also provides a deletion option, allowing you to remove the file from its servers. To delete the file, however, press the Delete icon. While this will disable the deletion link on the I Love PDF website, this does not guarantee that the file will be completely deleted from the site’s servers using this method.
As previously mentioned, you should not use services like I Love PDF for sensitive documents. For any kind of sensitive document containing personal data, you should use a software option to compress the file instead, such as the Preview or Free PDF Compressor apps demonstrated above.
Sharing And Viewing Compressed PDF Files
Compressing a PDF allows you to reduce the file size without lowering the quality too much (unless you want to). This makes it easier to share online, over email or other file sharing services. You can even password protect your PDF files to keep the contents of sensitive documents safe from snoopers.
If you’re struggling to open a PDF, you’ll need to install a good PDF reader like Adobe Acrobat or Foxit Reader. If you want an online option, you could convert PDFs to Google Docs, letting you view, edit, and share the files from your web browser without needing to install a third-party app first.
