What is Total Ink Coverage (TAC)?

TAC is the combined amount of ink in a given area of your PDF — the sum of C + M + Y + K values. For example: 100% cyan + 100% magenta + 100% yellow + 100% black = 400% TAC. That is too much for most printing methods; the ink cannot dry properly and will smear, stick together or crack on folds.

What is a safe threshold?

It depends on paper type and print method. The industry standard for coated offset is 300%. Uncoated paper or newsprint requires 240-280%. Premium paper can handle up to 340%. Ask your printer if unsure.

Why is too much TAC a problem?

Too much wet ink cannot soak into the paper. This leads to sheets sticking together in the delivery pile, set-off (ink transferring to the next sheet), extremely slow drying, cracking on folds, and show-through to the back. The result: your print job gets rejected or has to be reprinted.

What do the red areas in the heatmap mean?

Each pixel in your PDF is analyzed separately. The red areas are where the combined CMYK ink value exceeds your chosen threshold. Areas just over the threshold are orange/light red; the deeper the red, the worse the overage. Use the heatmap to pinpoint exactly where problems are in your design.

How do I avoid high TAC in my design?

Use rich black with moderate CMY values (e.g. C60 M40 Y40 K100 = 240%). Avoid registration black (100/100/100/100 = 400%) — it is only for crop marks. Check your RGB-to-CMYK conversions; dark photos can produce unexpectedly high TAC.

Yes — TAC check is free at pdf.dk. No watermark, no signup for basic use.

Check Total Ink Coverage in PDF

Check Total Ink Coverage in your PDF before printing. Find areas over 300% CMYK with a heatmap overlay. Free online preflight tool — required by most professional printers.

Frequently Asked Questions

What is Total Ink Coverage (TAC)?: TAC is the combined amount of ink in a given area of your PDF — the sum of C + M + Y + K values. For example: 100% cyan + 100% magenta + 100% yellow + 100% black = 400% TAC. That is too much for most printing methods; the ink cannot dry properly and will smear, stick together or crack on folds.
What is a safe threshold?: It depends on paper type and print method. The industry standard for coated offset is 300%. Uncoated paper or newsprint requires 240-280%. Premium paper can handle up to 340%. Ask your printer if unsure.
Why is too much TAC a problem?: Too much wet ink cannot soak into the paper. This leads to sheets sticking together in the delivery pile, set-off (ink transferring to the next sheet), extremely slow drying, cracking on folds, and show-through to the back. The result: your print job gets rejected or has to be reprinted.
What do the red areas in the heatmap mean?: Each pixel in your PDF is analyzed separately. The red areas are where the combined CMYK ink value exceeds your chosen threshold. Areas just over the threshold are orange/light red; the deeper the red, the worse the overage. Use the heatmap to pinpoint exactly where problems are in your design.
How do I avoid high TAC in my design?: Use rich black with moderate CMY values (e.g. C60 M40 Y40 K100 = 240%). Avoid registration black (100/100/100/100 = 400%) — it is only for crop marks. Check your RGB-to-CMYK conversions; dark photos can produce unexpectedly high TAC.
Is the tool free?: Yes — TAC check is free at pdf.dk. No watermark, no signup for basic use.

How to

Upload your PDF file
Choose your paper type (300% is the standard for coated offset)
Click "Analyze ink coverage"
Download the heatmap PDF and see exactly where the problems are