Javascripts supports precise numbers up to 9 007 199 254 740 992. Everything beyond that looses precision. I found myself loosing this precision when I had to parse a JSON with big numbers. A solution (although hacky) is to manually convert numbers to strings before parsing. Note: this will convert numbers to strings from 1 000 000 000 000 000 a…

big_number_to_string_in_json_string.js

var json_string = '{"big_number": 3754019163539080706}';

var json_string_converted = json_string
    .replace(/\s*:\s*(\d{16,})\s*\}/mg, ':"$1"}')
    .replace(/\s*:\s*(\d{16,})\s*\,/mg, ':"$1",');

var json = JSON.parse(json_string);
var json_converted = JSON.parse(json_string_converted);

console.log(json); // Precision lost
console.log(json_converted); // Precision not lost

// Converting back

var stringified = JSON.stringify(json_converted);

stringified = stringified
    .replace(/\s*:\s*"(\d{16,})"\s*\}/mg, ':$1}')
    .replace(/\s*:\s*"(\d{16,})"\s*\,/mg, ':$1,');

console.log(stringified); // Number type restored