diff --git a/README-flash_api.md b/README-flash_api.md
index bffed4a..7d1ce56 100644
--- a/README-flash_api.md
+++ b/README-flash_api.md
@@ -16,6 +16,7 @@ Legacy function for ESP8266 (not needed for ESP32)
 
 * __cgiUploadFirmware()__
 CGI function writes HTTP POST data to flash.
+A `CgiUploadFlashDef` must be passed as cgiArg with some options including callbacks.
 
 * __cgiRebootFirmware()__
 CGI function reboots the ESP firmware after a short time-delay.
diff --git a/include/libesphttpd/cgiflash.h b/include/libesphttpd/cgiflash.h
index 19ec12d..853209c 100644
--- a/include/libesphttpd/cgiflash.h
+++ b/include/libesphttpd/cgiflash.h
@@ -11,11 +11,22 @@ extern "C" {
 #endif
 
 typedef struct {
-	int type;
-	int fw1Pos;
-	int fw2Pos;
-	int fwSize;
-	const char *tagName;
+  const void *update_partition; // maybe useful info for the callback. Points to a esp_partition_t
+  int totalLen; // total length of the image in bytes
+  int received; // how much has been received so far
+} CgiUploadFlashStatus;
+
+typedef void(*CgiFlashUploadCb)(const CgiUploadFlashStatus *status);
+
+typedef struct {
+	int type; // CGIFLASH_TYPE_FW or CGIFLASH_TYPE_ESPFS
+	int fw1Pos; // not used for ESP32 FW
+	int fw2Pos; // not used for ESP32 FW
+	int fwSize; // not used for ESP32 FW
+	const char *tagName; // not used for ESP32
+	CgiFlashUploadCb beforeBeginCb; // Optional callback to be called before flash writing begins (i.e. shutdown unessary tasks)
+	CgiFlashUploadCb progressCb; // Optional callback to be called when upload progresses
+	CgiFlashUploadCb endCb; // Optional callback to be called after flash writing ends
 } CgiUploadFlashDef;
 
 CgiStatus cgiGetFirmwareNext(HttpdConnData *connData);
diff --git a/util/cgiflash.c b/util/cgiflash.c
index 9bc00c2..57d804f 100644
--- a/util/cgiflash.c
+++ b/util/cgiflash.c
@@ -221,6 +221,14 @@ CgiStatus ICACHE_FLASH_ATTR cgiUploadFirmware(HttpdConnData *connData) {
 			    else
 			    {
 			    	ESP_LOGI(TAG, "Writing to partition subtype %d at offset 0x%x", state->update_partition->subtype, state->update_partition->address);
+					// Check if there is a user callback for beginning the upload
+					if (def->beforeBeginCb) {
+						CgiUploadFlashStatus status = {0};
+						status.update_partition = state->update_partition;
+						status.totalLen = connData->post.len;
+						status.received = connData->post.received;
+						def->beforeBeginCb(&status);
+					}
 
 #ifdef CONFIG_ESPHTTPD_ALLOW_OTA_FACTORY_APP
 					// hack the API to allow write to the factory partition!
@@ -284,6 +292,15 @@ CgiStatus ICACHE_FLASH_ATTR cgiUploadFirmware(HttpdConnData *connData) {
 			}
 
 			dataLen = 0;
+			// Check if there is a user callback for progress
+			if (def->progressCb) {
+				CgiUploadFlashStatus status = {0};
+				status.update_partition = state->update_partition;
+				status.totalLen = connData->post.len;
+				status.received = connData->post.received;
+				def->progressCb(&status);
+			}
+			
 		} else if (state->state==FLST_DONE) {
 			ESP_LOGE(TAG, "%d bogus bytes received after data received", dataLen);
 			//Ignore those bytes.
@@ -319,6 +336,14 @@ CgiStatus ICACHE_FLASH_ATTR cgiUploadFirmware(HttpdConnData *connData) {
 			if (err != ESP_OK) {
 				ESP_LOGE(TAG, "esp_ota_set_boot_partition failed! err=0x%x", err);
 			}
+			// Check if there is a user callback for end of upload
+			if (def->endCb) {
+				CgiUploadFlashStatus status = {0};
+				status.update_partition = state->update_partition;
+				status.totalLen = connData->post.len;
+				status.received = connData->post.received;
+				def->endCb(&status);
+			}
 		}
 		cJSON_AddStringToObject(jsroot, "message", state->err);
 		cJSON_AddBoolToObject(jsroot, "success", (state->state==FLST_DONE)?true:false);