Understanding ArduinoJson capacity calculation assistant I am trying to figure out how ArduinoJson capacity can be calculated, therefore I came by the Assistant web application developed by the developer of the library https://arduinojson.org/v6/assistant/
Here what I do not understand is, why when I use either of the following two JSON strings, the helper shows me the same capacity? I would expect that the longer JSON values will result in a bigger capacity, but this does not seem to be the case.
{
  &quot;wifi&quot;: {
    &quot;ssid&quot;: &quot;S&quot;,
    &quot;password&quot;: &quot;P&quot;,
    &quot;hostname&quot;: &quot;H&quot;
  },
  &quot;administration&quot;: {
    &quot;username&quot;: &quot;U&quot;,
    &quot;password&quot;: &quot;P&quot;
  }
}

{
  &quot;wifi&quot;: {
    &quot;ssid&quot;: &quot;SSSSSSSSSSSSSSSSSSSSSSSSSSS&quot;,
    &quot;password&quot;: &quot;PPPPPPPPPPPPPPPPPPPPPPPPPP&quot;,
    &quot;hostname&quot;: &quot;HHHHHHHHHHHHHHHHHHHHHHHHHHHH&quot;
  },
  &quot;administration&quot;: {
    &quot;username&quot;: &quot;UUUUUUUUUUUUUUUUUUUUUUUUUUUUUU&quot;,
    &quot;password&quot;: &quot;PPPPPPPPPPPPPPPPPPPPPPPPPPPPPP&quot;
  }
}

I am trying to calculate the capacity using the assistant using the following configuration:
ESP8266 / Deserialize / char*
Could you anyone explain this to me? Apparently I understand the &quot;reason&quot; behind the capacity wrong?
If you look at the details of the numbers reported, you should see:
Data structures     112
Strings             0
Total (minimum)     112
Total (recommended) 128

As you see, there are exactly zero bytes allocated for the strings. This
means that the library does not copy the strings, and instead references
them from the character array you provide as an input.
If you instead configure the library for Stream input, it will have to
store the strings, and the capacity is then very different for these two
documents.