Max Character in JSON Parsing

Max Character in JSON Parsing

What is the max char in json parsing, and how to display large text like
800 char?
{
"employees": [
{
"firstName": "John",
"desc": null
},
{
"firstName": "Anna",
"desc": null
},
{
"firstName": "Peter",
"desc": null
}
]
}
I have problem when my database has 900 char the "JSON" showed null.