ablesen
to read off
To obtain and note a value from a measuring device, scale, or display.
Können Sie bitte den Stand vom Wasserzähler ablesen?
Could you please read off the reading from the water meter?

to read off
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to read off
To obtain and note a value from a measuring device, scale, or display.
Können Sie bitte den Stand vom Wasserzähler ablesen?
Could you please read off the reading from the water meter?

'Ablesen' is a separable verb. In a main clause, the prefix 'ab-' comes at the end of the sentence. In subordinate clauses or in the infinitive with 'zu', it stays together with the verb.
Er liest den Stromverbrauch am Zähler ab.
He reads off the electricity consumption from the meter.
The prefix 'ab-' in combination with 'lesen' (to read) conveys the idea of 'removing' or grasping information from a surface. This applies to a meter, a sheet of paper, or even a face.
Die Ärztin las die Werte vom Monitor ab.
The doctor read the values off the monitor.
When recognizing a person's feelings or thoughts, a dative construction is used: 'jemandem (dative) etwas vom Gesicht/von den Augen ablesen' (to read something from someone's face/eyes).
Ich konnte meiner Freundin die Freude vom Gesicht ablesen.
I could read the joy on my friend's face.
The object reveals the meaning: A measuring device ('Zähler' (meter), 'Uhr' (clock/watch/gauge)) points to reading off values. A text ('Blatt' (sheet of paper), 'Rede' (speech)) means reading aloud. A face or eyes point to recognizing feelings.
Bitte lies die Temperatur vom Thermometer ab.
Please read the temperature off the thermometer.
When someone has to 'ablesen' (read out) a speech, it often has a slightly negative meaning. It can suggest uncertainty, nervousness, or a lack of preparation.
Der Redner wirkte nicht überzeugend, da er alles nur ablas.
The speaker did not seem convincing because he only read everything out.
to read
'lesen' and 'ablesen' can both mean obtaining information from signs, numbers, or data. 'lesen' is more general here: you can read and understand a text, a map, or data. 'ablesen' is used more specifically when you take a particular value from a measuring device, a scale, or a display. Learners may confuse the words because both have to do with numbers or information. For an electricity meter, a thermometer, or a display, 'ablesen' usually fits better.

In der Küche liest Maria die Temperatur am Thermometer ab.
In the kitchen, Maria reads the temperature off the thermometer.
Morgen liest er die Karte genau, damit das Team den richtigen Weg findet.
Tomorrow he will read the map carefully so that the team finds the right way.