Contrast: What Does It Mean?

The setting that lightens or darkens a scanned page before a fax goes out.

Sarah Mitchell

Published on

September 9, 2026

Last updated on

September 11, 2026

Contrast is a fax setting that lightens or darkens a scanned page before it's transmitted, used to compensate for a document that's too faint or too dark in the original.
A low-contrast original, like a faded printout, often needs a darker setting so the received fax stays legible.
Contrast is a sender-side adjustment made before transmission, not something the recipient can change after the fax arrives.

What Does Contrast Mean on a Fax?

Contrast is a setting that lightens or darkens a scanned page before it's transmitted, used to compensate for an original document that's too faint or too dark to read clearly once faxed. It's typically offered alongside resolution settings as one of the two main image-quality adjustments available before sending.

When Contrast Actually Matters

A faded printout or a document photocopied one generation too many times often needs a darker contrast setting so faint text doesn't disappear entirely once it's compressed for transmission. A document with heavy ink or shading sometimes needs the opposite, a lighter setting, to keep the page from arriving as a solid block of toner. Most devices also offer an automatic setting that adjusts contrast based on the scanning step before a fax is sent, without requiring a manual choice.

Contrast Is a Sender-Side Setting

Contrast is adjusted before a fax is sent, not something a recipient can change after it arrives. Once a page has been transmitted at a given contrast level, that's the version the recipient receives. It's a distinct concept from gray-scale conversion, which controls how many shades of gray a scanned image is allowed to use, rather than how light or dark the whole page reads.

A Common Case: Rescuing a Faded Original Before Faxing It

An administrative assistant needs to fax a decades-old contract that's badly faded from years in a filing cabinet. Setting the fax machine's contrast to its darker option before sending keeps the text legible on the receiving end, instead of the barely-readable page a default setting would have produced.

FAQs

How do I make a faxed document lighter or darker?

Most fax machines and online fax services offer a contrast setting, usually Auto, Light, or Dark, that adjusts the page before it's sent to keep faded or overly dark originals legible.