Calculate the ink coverage of a PDF
Ink coverage is the share of a page's area that ink or toner has to cover when the page is printed. This calculator renders each PDF page in your browser, averages the darkness of every pixel into a per-page coverage percentage, and rates each page in plain language — under 3% is a typical text page. The full per-page table exports as CSV for print-cost estimates, and the file never leaves your device.
How it works
Printer economics are built around coverage. When a manufacturer rates a toner cartridge at, say, 1,500 pages, that figure assumes each page uses about 5% coverage — the industry's standard test document, roughly a short business letter. Your real documents rarely match that assumption: sparse text pages use less, charts and photos use far more, and the difference is the gap between the rated yield and the number of pages you actually get.
This calculator makes the number concrete per page. Each page is rendered to a canvas by pdf.js, the pixel data is read back, and every pixel's darkness is computed from its luminance — a pure white pixel contributes 0%, solid black contributes 100%, and a mid-gray or saturated color lands in between. The page's coverage is the average of all pixel darkness values across its area. Alongside the percentage, each page gets a plain-language assessment: a page under 3% reads as a typical text page, higher bands flag graphics-heavy and photo-heavy pages that will drain a cartridge quickly.
One caveat matters for print professionals: this is composite darkness measured from the rendered page, not a prepress ink-key report. A press RIP separates each page into cyan, magenta, yellow and black plates and reports coverage per plate, where a saturated color area can total far more than 100% across the four inks. A single composite number cannot capture that, so use these figures to budget desktop laser and inkjet printing, compare documents, and spot expensive pages — and use your print provider's preflight for plate-level data. For cutting the cost itself, converting the file with the grayscale tool before printing avoids color ink entirely.
Worked example: budgeting a client proposal print run
A 14-page proposal (5.2 MB) was analyzed before printing 40 copies. The eleven text pages measured between 2.1% and 3.4% coverage; a bar-chart page scored 8.7%; a page with two product photos reached 19%; and the full-bleed cover photo hit 46%. Exported to CSV and totaled, the document averaged 7.9% per page — the cover alone consumed as much toner as roughly nine rated pages. Against a cartridge quoted at 1,500 pages at 5% coverage and costing $80 (about 5.3 cents per rated page), one copy worked out to approximately 22 rated-page equivalents, or $1.17 in toner — about $47 for the run of 40, with the cover accounting for nearly a third of it. Printing the cover in color and the body on a cheaper mono device cut the estimate almost in half.
Frequently asked questions
What is a normal ink coverage for a text page?
An ordinary page of black text typically measures under 3% coverage. Cartridge page yields are usually quoted at 5% coverage, so plain text documents print more pages per cartridge than the box suggests.
Does this tool measure the CMYK plates separately?
No. It measures composite darkness of the rendered page, not the separated cyan, magenta, yellow and black plates a press or RIP would report. Treat the numbers as a practical estimate for desktop printing rather than prepress ink-key data.
How do I turn the percentages into a printing cost estimate?
Divide a page's coverage by the 5% reference used for cartridge yields to see how many standard pages it consumes; a 15% page uses roughly three times the toner of a rated page. Multiply by your cost per rated page, which is the cartridge price divided by its quoted yield.
Why does a light gray page background raise coverage so much?
Coverage averages the darkness of every pixel, and a tinted background adds a little darkness across the entire page area. Even a 10% gray tint over a full page adds around ten percentage points, dwarfing the text on top of it.
Can I export the per-page results?
Yes, the whole table downloads as a CSV file with one row per page. That makes it easy to total a print job or compare document versions in a spreadsheet.