Custom Chunk Size

Demo uploads land in a temporary store and are swept after 60 minutes. To keep files, handle FileUploaded — see Single File for the complete save pattern.

Custom Chunk Size

Configure the chunk size used during chunked uploads. Smaller chunks provide more granular progress feedback while larger chunks reduce HTTP overhead. Choose a size that balances your network conditions and user experience.

What you should see: 1 MB chunks instead of the default 5 MB. Pick a multi-megabyte file and the network panel shows several numbered chunk POSTs plus one completion call.

Select Chunk Size

Current chunk size: 1 MB

var uploader = AjaxUploader.create('#uploader', {
 uploadUrl: '/ajaxupload.axd/upload',
 chunkUrl: '/ajaxupload.axd/chunk',
 chunkCompleteUrl: '/ajaxupload.axd/chunk/complete',
 chunked: true,
 chunkSize: 1 * 1024 * 1024, // 1 MB
 multiple: true,
 onTaskProgress: function(task) {
 status.textContent = task.fileName + ': ' +
 clampPercent(task.percent) + '% (' +
 AjaxUploader.formatSize(task.loaded) + ')';
 },
 onTaskComplete: function(task) {
 status.textContent = task.fileName + ' uploaded successfully.';
 }
});