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Is there a tool or something that will give me the value of the pixel under the cursor? What I've got in mind in something like the eyedropper tool in graphics programs that allows you to interactively sample points in a raster image.

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In QGIS you can use the "identify tool" that give you the value where you click (very left on the image, which comes from QGIS 1.6. It looks a bit different with other version). This work both for raster and feature layers. You can also use the shortcut "Ctrl+Shift+I". In QGIS 2.0, you can save the results using "copy attributes" at the bottom of the identify pop up.

button on the left for identify (QGIS 1.6)

You can configure the identify tool and select the layers that you want to identify. Note that in QGIS 3, you can also select the "table" or "graphic" views, which shows all layers in a similar way than the "Value Tool". The main difference with the "value tool" is that the "Value tool" continuously update while the identify tool needs a click (then remains unchanged until you click again).

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  • don't see how I missed this. I even tried the identity tool and only noticed the layer name. Now that I tried again, I see that there is a value column as well. – Llaves Feb 7 '14 at 16:23
  • The Values tool suggested by nhopton seems infinitely easier to use: you don't have to figure out what layer a point is on. – Richard Jul 17 '16 at 23:14
  • @Richard you can configure the identify tool. I find it quite usefull to be able to identify only one layer (especially when I have some very large layers which slow down the queries). The difference with the Value tool is that the value tool use all layers by default while the value tool uses 1 layer by default. But they both have similar configuration. The "ease of use" is quite subjective now that the identify tool has been improved. – radouxju Jul 2 '18 at 10:17
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The Value Tool should do what you want. Install it from the Plugins menu, then enable it: View -> Panels -> Value Tool.

N.

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  • 1
    Good answer, but Value tool is not installed by default. I would edit it to include that. – Alexandre Neto Feb 7 '14 at 9:53
  • I have no objection to solutions that require a plug-in, esp when they introduce me to a capability I wasn't aware of. The only reason I didn't select this as "the answer" is that the identify tool, being built-in, seems the more correct choice. But I certainly liked this enough to up-vote it. – Llaves Feb 7 '14 at 16:53
  • The value tool's sooo much better: I don't have to figure out what layer needs to be selected to get its values. – Richard Jul 17 '16 at 23:14
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you can use point sampling tool in Qgis , it will extract raster values to point shapefile. you have to provide the point shapefile for sampling location.

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  • Voted down, because user has asked specifically for QGis solution. – Zbynek Feb 7 '14 at 6:38
  • If QGIS had been mentioned in the body of the Question then I would have downvoted too, but it was only there as a tag (and easily overlooked by a new user of our site) so I'll stay neutral. You should have an option to delete your Answer if you want to. – PolyGeo Feb 7 '14 at 6:46
  • i didnt see the tag just answered the question.. will try to be careful next time.. editing my answer – Saad Ali Feb 7 '14 at 7:09

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