How do you check ink level in ph photosmart 3100

If you have it connected to a computer then the HP utilities should be able to show the ink levels. You can also check the printer properties in the driver for a maintenance tab that should show ink levels as well.

All the information you require to check ink levels for the printer are available at this HP support website. Make sure you expand the links at the bottom of that page.
Check Ink Levels

To check the ink levels from the printer control panel
1. Press Setup.
2. Press the down arrow button to highlight Tools, and then press OK.
3. Press the down arrow button to highlight Display Ink Gauge, and then press OK.
The product displays a gauge that shows the estimated ink levels of all cartridges
installed.
4. Press any button to return to the Tools menu.
To check the ink levels from the HP Photosmart Software
1. In the HP Solution Center, click Settings, point to Print Settings, and then click
Printer Toolbox.
NOTE: You can also open the Printer Toolbox from the Print Properties dialog
box. In the Print Properties dialog box, click the Features tab, and then click the
Printer Services button.
The Printer Toolbox appears.
2. Click the Estimated Ink Level tab.
The estimated ink levels for the ink cartridges appear.
Replace the ink cartridges

To check the ink levels from the control panel

1. Press Setup.

2. Press the down arrow button to highlight Tools, and then press OK.

3. Press the down arrow button to highlight Display Ink Gauge, and then press OK. The product displays a gauge that shows the estimated ink levels of all cartridges installed.

4. Press any button to return to the Tools menu.

To check the ink levels from the HP Photosmart Software

1. In the HP Solution Center, click Settings, point to Print Settings, and then click Printer Toolbox.

NOTE: You can also open the Printer Toolbox from the Print Properties dialog box. In the Print Properties dialog box, click the Features tab, and then click the Printer Services button.

The Printer Toolbox appears.

2. Click the Estimated Ink Level tab. The estimated ink levels for the ink cartridges appear.

Not all printers have this option, but i think this one should. you may need to download and install the software, you can do that from here: http://h10025.www1.hp.com/ewfrf/wc/softwareList?os=228&lc=en&dlc=en&cc=id〈=en&product=1153494
Try the HP Photosmart Full Feature Software and Drivers and the HP Printing Diagnostic Utility
give that a go. Hope this helps

Check and download the utility from vendor site to check the ink levels.

click on the below link for the information.
http://h10025.www1.hp.com/ewfrf/wc/document?docname=c00705968&cc=us&lc=en&dlc=en&product=1153481

Download an instruction Manual for your model priinter:
http://h10025.www1.hp.com/ewfrf/wc/product?product=3418705&lc=en&cc=us&dlc=en&submit.y=6&submit.x=5〈=en&cc=us 

open the printer software check the catridge level.it willl help u.

If your HP is installed you have "HP digital imaging monitor" on your toolbar.
1. right click, you will see "HP Photosmart..." - "Display status"
2. Click "View Ink Levels"