how do I export a .jpg file with at least <70kb out of photoshop?

[MessainMotion]

how do I export a .jpg file with at least <70kb out of photoshop?

[c.pfaffenbichler]

The issue of exporting to size has come up repeatedly but as far as I can tell none of the regulars has considered it interesting enough to pursue on this Forum.

A Scriptable approach (export, check size, if necessary scale and/or export with different settings, check size, …) is evident.

It may not be "fast", though.

[I have gone]

Here is an example that will try to reach the given size in steps of 4 in quality.

var saveFile = File(Folder.desktop + "/test");
var fileSize = 70;
try{
tmpFile = File(saveFile+".jpg");
for(var z =100;z>5;z -=4){
SaveForWeb(tmpFile,z);
var chkFile = File(saveFile+".jpg");
//$.writeln(tmpFile + " qual = " + z + " Size = " +(chkFile.length/1024).toFixed(2) + "k" ); 
if((chkFile.length/1024).toFixed(2) < (fileSize +1)) break;
tmpFile.remove();
}
if(!tmpFile.exists)  SaveForWeb(tmpFile,5);
}catch(e){$.writeln(e + " - " + e.line);}


function SaveForWeb(saveFile,jpegQuality) {
var sfwOptions = new ExportOptionsSaveForWeb(); 
   sfwOptions.format = SaveDocumentType.JPEG; 
   sfwOptions.includeProfile = false; 
   sfwOptions.interlaced = 0; 
   sfwOptions.optimized = true; 
   sfwOptions.quality = Number(jpegQuality); 
activeDocument.exportDocument(saveFile, ExportType.SAVEFORWEB, sfwOptions);
};

[xbytor2]

This response, barring any errors, is the correct answer. It would be far easier if there were an ExportOptionsSaveForWeb.maxSize option, but there isn't.