Why toner density changes across a full page

A page starts dark on one side and fades toward the other, or a band of text looks lighter than the rest. If toner density changes across a full page, it can be hard to tell whether the cause is a setting, the paper, or a printer part.

Print a consistent test pattern before changing anything. The Printer Test Page includes color blocks, gray steps, lines, and text that help you see where the change occurs.

Print a page you can compare

Open the Printer Test Page and print it from your browser.
Use plain, clean paper that the printer supports. In the print dialog, select the correct paper size and type, and avoid options such as draft or toner saving for this first check.
Look at the printed page in ordinary, even light. Check the gray steps and large blocks first, then look for changes in the text and lines.
Note where the change appears: across the page from left to right, from top to bottom, in a stripe, or in a pattern that repeats.
If the first page looks uneven, print the same test once more without changing settings. Compare the same areas on both pages.

Keep the sheet in the same orientation as it came out of the printer. The paper feed direction matters when you describe where a stripe or fade appears.

What the result means

The whole page is evenly pale

If gray blocks, text, and lines are all consistently light, check print quality settings and toner status first. A low or poorly distributing cartridge is also possible, but a uniformly pale page alone does not prove that the cartridge is empty.

One side is darker than the other

A gradual change from one side to the other can point to uneven toner distribution or a problem in the cartridge or imaging path. It can also come from the paper being the wrong type or damp. If the same gradient appears on a second test page, the printer is more likely to be the source than the document.

A clear stripe crosses the page

A sharp light or dark stripe suggests a localized issue. A toner cartridge, drum, transfer component, or another part may be involved. The direction and spacing of the stripe can help a repair technician, but the test page cannot identify a failed part by itself.

The same mark repeats at regular intervals

Repeated marks may come from a rotating part such as a drum or roller. Measure the distance between marks and keep the page as evidence. If the spacing stays the same on another print, check the printer's maintenance instructions or ask a service technician to interpret it.

The test looks even, but your document does not

The printer can produce an even pattern, so look at the document, application, or print settings. A low-opacity image, colored background, or different paper setting can make one area seem lighter even when the printer is working consistently.

How to fix uneven toner density

Check the paper. Use dry paper that matches the size and type selected in the print dialog. Paper stored in a damp place or a type the printer does not support can affect toner transfer.
Turn off draft or toner saving. On Windows 11, open Settings › Bluetooth & devices › Printers & scanners, choose your printer, then open its printing preferences. On macOS, open the print dialog and look under Printer Options or Media & Quality. Driver names differ, so check for draft, economy, or toner-saving options.
Confirm the selected paper type. Choose the paper type that matches what is loaded. A mismatch can change how the printer applies and fixes toner. Check the printer's own display or driver if it offers a separate paper setting.
Check the printer's toner status. Use the printer display or its status software. A low-toner warning is useful evidence, but remaining toner estimates are not precise measurements of print density.
Reseat the cartridge only as the manual allows. Turn the printer off if its instructions say to do so, and follow the model's steps. Avoid touching the drum or exposed imaging surfaces. Do not shake a cartridge unless the manufacturer specifically recommends it.
Run only the maintenance procedure for your model. Use the printer's documented cleaning or calibration option if it has one. Avoid repeated maintenance cycles, which can consume toner without fixing a worn part.
Test another cartridge or arrange service. If the same uneven pattern remains with supported paper and normal-quality settings, a cartridge or printer component may need replacement or repair.

When the printer may need repair

If the same stripe, fade, or repeating mark appears on multiple test pages, after checking the paper and settings, the issue is probably inside the printer or cartridge. A replacement cartridge can help identify a cartridge fault if you have a compatible one available. If the defect remains, contact the printer manufacturer or a repair shop with the test pages and a note about the pattern. Do not open a printer's hot areas or handle internal parts unless its instructions say they are safe to access.

Why a test pattern helps

A document can hide printer problems because different sections use different amounts of toner. The Printer Test Page puts solid areas, gray tones, lines, and text on one sheet, making it easier to compare across the page. It helps narrow down the cause, but it cannot measure toner concentration or confirm that a particular component is defective.