What the best scanner has
- High scanning and processing speed. Especially for document scanners, you want pages to go through as quickly as possible while still producing good results. However, calculating the page-per-minute (ppm) rate can be tricky, as higher-resolution scans take more time. So when you look at scanners, make sure the ppm rates you're comparing are for the same type of document and resolution – for instance, a single four-color page at 300 ppi.
- Accurate OCR. If you want to convert scanned text into an editable document, you also need optical character recognition (OCR) software, which is included with many document scanners. Some scanner makers use their own OCR software, while others license it from a third party. Either approach works as long as the software is accurate – and is updated frequently enough to work with the latest version of your computer's operating system.
- Jam-free operation. For document scanning, the best scanners have a high-capacity feed tray that allows you to set up a stack of pages and go. Once they get started on a stack, they should be able to finish without jamming, sticking, or pulling paper in crooked.
- A good warranty. A one-year warranty – the standard for better-quality scanners in our report –should be your minimum bar for a new scanner.
Know before you go
What do you need to scan? What type of scanner you need largely depends on what, as well as how often, you'll need to scan. Flatbed scanners are the most practical for multipurpose use. They're generally more versatile and cheaper than scanners geared toward a specific function. They're a safe bet if you'll be scanning delicate material such as photos, film or slides, and they're essential for handling 3D objects or bound material like books and magazines. Those who need to create digital copies of lots of loose pages and documents should consider a sheet-fed document scanner, which is designed specifically for this task. High-end photo scanners are relatively expensive, but they're the best for high-resolution scans of images. They're also ideal for scanning film, slides, or negatives, although some basic flatbed scanners can handle these materials also.
What resolution do you need? If you're scanning plain-text documents or documents with business graphics, resolution isn't a huge concern – experts say 200 dpi is adequate, and 300 dpi is plenty. New scanners typically have resolutions of least 600 dpi, which is sufficient for images, as long you don't enlarge them too much or zoom in too far. For the finest detail or printing scans at a larger size, you'll need a scanner with a higher claimed resolution – at least 4,800 dpi. Reviews note that you should take claimed resolutions with a grain of salt, as these specs are often inflated or are bottlenecked by the scanner's optical hardware. However, as a rule of thumb, the higher a scanner's claimed resolution, the higher its real-world resolution is likely to be.
Do you scan in bulk? If you plan to churn through huge stacks of paper on a regular basis, an automatic document feeder (ADF) is a must. Look for an ADF with a capacity greater than or equal to the number of pages you typically need to scan at a go. If you have to scan a longer document once in a while, you can always add more pages partway through the process.
How big are your documents? The larger the scanning area, the larger the document or photo you can reproduce (and the larger number of smaller images you can scan at a time). Most flatbed scanners can only accommodate letter-size documents, so if you need to scan legal-size pages or large pieces of artwork, look for a larger scanbed.
Do you need duplex scanning? There are several ways to scan two-sided documents. True duplexing scanners have two scanning elements, so they can scan both sides of a page at once. Other scanners have an ADF with duplexing capabilities; it scans one side of the page, flips it, and scans the other. Duplexing scanners are faster, but they're also more expensive. If cost is a concern, a cheaper alternative is a basic scanner with a manual duplexing feature in its driver. With this feature, you scan in a stack of pages, flip it over, and scan the other side, and the software automatically interleaves the pages. This is a good choice if you only need to scan two-sided documents once in a while.
What operating system are you using? Most scanners work with recent versions of Windows, but if you're using a Mac or Linux system, double-check to make sure the scanner is compatible with it. We saw many complaints from Mac users who bought scanners only to discover that they weren't compatible with the latest version of the Mac OS – or, in other cases, with older versions. Also, if you run into issues, check the manufacturer's web site before throwing in the towel to make sure you are using the latest driver version for your scanner.
How much space can you spare? A final consideration is size.Many owners appreciate a scanner that doesn't take up too much valuable desk space. It's also handy to have trays and other extensions that fold up into a more compact form when the scanner isn't in use.