how to get character count

app.findGrepPreferences = app.changeGrepPreferences = null;
app.findChangeGrepOptions.includeMasterPages = true; //false, if you don't want to include master pages
app.findChangeGrepOptions.includeFootnotes = true; //false, if you don't want to include footnotes
app.findChangeGrepOptions.includeHiddenLayers = true; //false, if you don't want to include hidden layers
//for find GREP only:
app.findChangeGrepOptions.includeLockedLayersForFind = true; //false, if you don't want to include locked layers
//for find GREP only:
app.findChangeGrepOptions.includeLockedStoriesForFind = true; //false, if you don't want to include locked stories
app.findGrepPreferences.findWhat = "\.";
var _d = app.documents[0];
//That will find too much:
var _resultLength = _d.findGrep().length;
app.findGrepPreferences = app.changeGrepPreferences = null;
//Let's EXCLUDE special characters of anchored or inline objects:
app.findGrepPreferences.findWhat = "\uFFFC";
//A second search will correct that:
var _resultSpecialCharacter = _d.findGrep().length;
alert("Total:"+"\t"+(_resultLength - _resultSpecialCharacter)+" "+"characters");
app.findGrepPreferences = app.changeGrepPreferences = null;

And here we have a version that will EXCLUDE texts on the pasteboard (we can further refine it if we want to exclude special characters for text variables like "File Name" etc.pp.). The script is CS5 and CS5.5 only:

//CountTotalCharactersOfPages.jsx
//DESCRIPTION:Excludes all texts on the pasteboard; hidden texts on pages will be counted; every instance of a used text variable will be counted as one character!
//Uwe Laubender
/**
* @@@BUILDINFO@@@ CountTotalCharactersOfPages.jsx !Version! Wed Jan 25 2012 16:08:46 GMT+0100
*/
//IDEA:
//To mask text frames on the pasteboard:
//1. we have to move them to a special layer
//2. lock that layer
//3. change the search so that locked layers are excluded
//After returning the result, go back to the old state
app.scriptPreferences.userInteractionLevel = UserInteractionLevels.interactWithAll;
if(parseFloat(app.version)<7){
    alert("Your InDesign app version should be version 7 (CS5) or 7.5 (CS5.5)");
    exit();
    };
if(parseFloat(app.version)>7.6){
    alert("Script is not tested for InDesign above version 7.5 (CS5.5)");
    exit();
    };
app.doScript(_CountCharacters, undefined, app.selection[0], UndoModes.entireScript, "Count characters");
//One undo will get you back to the initial state of the document:
app.undo();
function _CountCharacters(){
var _d = app.documents[0];
//Add a new layer; if it's already there set the variable to that layer:
try{
    var _pasteBoardItemsLayer = _d.layers.add({name:"PasteBoardItems"});
    }catch(e){
        alert("There already is a layer named PasteBoardItems; rename it and try again!");
        exit();
        };
//Unlock ALL layers in one go:
_d.layers.everyItem().locked = false;
//Put all pasteboard items to that layer "PasteBoardItems":
for(var n=0;n<_d.pageItems.length;n++){
    if(_d.pageItems.parentPage === null){
        _d.pageItems.locked = false;
        _d.pageItems.itemLayer = _pasteBoardItemsLayer;
        };
    };
//Lock the _pasteBoardItemsLayer:
_pasteBoardItemsLayer.locked = true;
app.findGrepPreferences = app.changeGrepPreferences = null;
app.findChangeGrepOptions.includeMasterPages = true; //false, if you don't want to include master pages
app.findChangeGrepOptions.includeFootnotes = true; //false, if you don't want to include footnotes
app.findChangeGrepOptions.includeHiddenLayers = true; //false, if you don't want to include hidden layers
//for find GREP only:
//Do NOT include locked layers in the search:
app.findChangeGrepOptions.includeLockedLayersForFind = false; //true, if you want to include locked layers
//for find GREP only:
app.findChangeGrepOptions.includeLockedStoriesForFind = true; //false, if you don't want to include locked stories
app.findGrepPreferences.findWhat = "\.";
//That will find too much:
var _resultLength = _d.findGrep().length;
app.findGrepPreferences = app.changeGrepPreferences = null;
//Let's EXCLUDE special characters of anchored or inline objects:
app.findGrepPreferences.findWhat = "\uFFFC";
//A second search will correct that:
var _resultSpecialCharacter = _d.findGrep().length;
alert("Total:"+"\t"+(_resultLength - _resultSpecialCharacter)+" "+"characters");
app.findGrepPreferences = app.changeGrepPreferences = null;
};

"White space" characters are counted, paragraph returns or soft returns are NOT counted.

Uwe