diff --git a/src/tool_writeout.c b/src/tool_writeout.c
index 9fbc8665d0..32c95b45ff 100644
--- a/src/tool_writeout.c
+++ b/src/tool_writeout.c
@@ -55,13 +55,13 @@ static const struct writeoutvar variables[] = {
   {"size_request", VAR_REQUEST_SIZE, 0,
    CURLINFO_REQUEST_SIZE, JSON_LONG},
   {"size_download", VAR_SIZE_DOWNLOAD, 0,
-   CURLINFO_SIZE_DOWNLOAD_T, JSON_LONG},
+   CURLINFO_SIZE_DOWNLOAD_T, JSON_OFFSET},
   {"size_upload", VAR_SIZE_UPLOAD, 0,
-   CURLINFO_SIZE_UPLOAD_T, JSON_LONG},
+   CURLINFO_SIZE_UPLOAD_T, JSON_OFFSET},
   {"speed_download", VAR_SPEED_DOWNLOAD, 0,
-   CURLINFO_SPEED_DOWNLOAD_T, JSON_TIME},
+   CURLINFO_SPEED_DOWNLOAD_T, JSON_OFFSET},
   {"speed_upload", VAR_SPEED_UPLOAD, 0,
-   CURLINFO_SPEED_UPLOAD_T, JSON_TIME},
+   CURLINFO_SPEED_UPLOAD_T, JSON_OFFSET},
   {"content_type", VAR_CONTENT_TYPE, 0,
    CURLINFO_CONTENT_TYPE, JSON_STRING},
   {"num_connects", VAR_NUM_CONNECTS, 0,
diff --git a/src/tool_writeout.h b/src/tool_writeout.h
index 64d7595751..a21787ab9a 100644
--- a/src/tool_writeout.h
+++ b/src/tool_writeout.h
@@ -65,6 +65,7 @@ typedef enum {
   JSON_NONE,
   JSON_STRING,
   JSON_LONG,
+  JSON_OFFSET,
   JSON_TIME,
   JSON_VERSION,
   JSON_FILENAME
diff --git a/src/tool_writeout_json.c b/src/tool_writeout_json.c
index 70235c2091..dfe51b9ffa 100644
--- a/src/tool_writeout_json.c
+++ b/src/tool_writeout_json.c
@@ -105,7 +105,7 @@ static int writeString(FILE *str, CURL *curl, const char *key, CURLINFO ci)
 
 static int writeLong(FILE *str, CURL *curl, const char *key, CURLINFO ci)
 {
-  curl_off_t val = 0;
+  long val = 0;
   if(CURLE_OK == curl_easy_getinfo(curl, ci, &val)) {
     fprintf(str, "\"%s\":%ld", key, val);
     return 1;
@@ -113,6 +113,16 @@ static int writeLong(FILE *str, CURL *curl, const char *key, CURLINFO ci)
   return 0;
 }
 
+static int writeOffset(FILE *str, CURL *curl, const char *key, CURLINFO ci)
+{
+  curl_off_t val = 0;
+  if(CURLE_OK == curl_easy_getinfo(curl, ci, &val)) {
+    fprintf(str, "\"%s\":%" CURL_FORMAT_CURL_OFF_T, key, val);
+    return 1;
+  }
+  return 0;
+}
+
 static int writeFilename(FILE *str, const char *key, const char *filename)
 {
   if(filename) {
@@ -160,6 +170,9 @@ void ourWriteOutJSON(const struct writeoutvar mappings[], CURL *curl,
     case JSON_LONG:
       ok = writeLong(stream, curl, name, cinfo);
       break;
+    case JSON_OFFSET:
+      ok = writeOffset(stream, curl, name, cinfo);
+      break;
     case JSON_TIME:
       ok = writeTime(stream, curl, name, cinfo);
       break;
diff --git a/tests/data/test970 b/tests/data/test970
index 04a663bc9f..54e34cc5b3 100644
--- a/tests/data/test970
+++ b/tests/data/test970
@@ -60,7 +60,7 @@ Accept: */*
 
 </protocol>
 <stdout nonewline="yes">
-{"url_effective":"http://%HOSTIP:%HTTPPORT/970","http_code":200,"response_code":200,"http_connect":0,"time_total":0.000013,"time_namelookup":0.000013,"time_connect":0.000013,"time_appconnect":0.000013,"time_pretransfer":0.000013,"time_starttransfer":0.000013,"size_header":4019,"size_request":4019,"size_download":445,"size_upload":0,"speed_download":0.000013,"speed_upload":0.000013,"content_type":"text/html","num_connects":1,"time_redirect":0.000013,"num_redirects":0,"ssl_verify_result":0,"proxy_ssl_verify_result":0,"filename_effective":"log/out970","remote_ip":"%HOSTIP","remote_port":%HTTPPORT,"local_ip":"127.0.0.1","local_port":13,"http_version":"1.1","scheme":"HTTP","curl_version":"curl-unit-test-fake-version"}
+{"url_effective":"http://%HOSTIP:%HTTPPORT/970","http_code":200,"response_code":200,"http_connect":0,"time_total":0.000013,"time_namelookup":0.000013,"time_connect":0.000013,"time_appconnect":0.000013,"time_pretransfer":0.000013,"time_starttransfer":0.000013,"size_header":4019,"size_request":4019,"size_download":445,"size_upload":0,"speed_download":13,"speed_upload":13,"content_type":"text/html","num_connects":1,"time_redirect":0.000013,"num_redirects":0,"ssl_verify_result":0,"proxy_ssl_verify_result":0,"filename_effective":"log/out970","remote_ip":"%HOSTIP","remote_port":%HTTPPORT,"local_ip":"127.0.0.1","local_port":13,"http_version":"1.1","scheme":"HTTP","curl_version":"curl-unit-test-fake-version"}
 </stdout>
 </verify>
 </testcase>