diff --git a/src/stats.c b/src/stats.c
index fac54ad3..e70a567c 100644
--- a/src/stats.c
+++ b/src/stats.c
@@ -408,21 +408,47 @@ stats_arena_bins_print(emitter_t *emitter, bool mutex, unsigned i) {
 }
 
 static void
-stats_arena_lextents_print(void (*write_cb)(void *, const char *),
-    void *cbopaque, bool json, unsigned i) {
+stats_arena_lextents_print(emitter_t *emitter, unsigned i) {
 	unsigned nbins, nlextents, j;
 	bool in_gap, in_gap_prev;
 
 	CTL_GET("arenas.nbins", &nbins, unsigned);
 	CTL_GET("arenas.nlextents", &nlextents, unsigned);
-	if (json) {
-		malloc_cprintf(write_cb, cbopaque,
-		    "\t\t\t\t\"lextents\": [\n");
-	} else {
-		malloc_cprintf(write_cb, cbopaque,
-		    "large:          size ind    allocated      nmalloc"
-		    "      ndalloc    nrequests  curlextents\n");
-	}
+
+	emitter_row_t header_row;
+	emitter_row_init(&header_row);
+	emitter_row_t row;
+	emitter_row_init(&row);
+
+#define COL(name, left_or_right, col_width, etype)			\
+	emitter_col_t header_##name;					\
+	emitter_col_init(&header_##name, &header_row);			\
+	header_##name.justify = emitter_justify_##left_or_right;	\
+	header_##name.width = col_width;				\
+	header_##name.type = emitter_type_title;			\
+	header_##name.str_val = #name;					\
+									\
+	emitter_col_t col_##name;					\
+	emitter_col_init(&col_##name, &row);				\
+	col_##name.justify = emitter_justify_##left_or_right;		\
+	col_##name.width = col_width;					\
+	col_##name.type = emitter_type_##etype;
+
+	COL(size, right, 20, size)
+	COL(ind, right, 4, unsigned)
+	COL(allocated, right, 13, size)
+	COL(nmalloc, right, 13, uint64)
+	COL(ndalloc, right, 13, uint64)
+	COL(nrequests, right, 13, uint64)
+	COL(curlextents, right, 13, size)
+#undef COL
+
+	/* As with bins, we label the large extents table. */
+	header_size.width -= 6;
+	emitter_table_printf(emitter, "large:");
+	emitter_table_row(emitter, &header_row);
+	emitter_json_arr_begin(emitter, "lextents");
+
 	for (j = 0, in_gap = false; j < nlextents; j++) {
 		uint64_t nmalloc, ndalloc, nrequests;
 		size_t lextent_size, curlextents;
@@ -436,38 +462,35 @@ stats_arena_lextents_print(void (*write_cb)(void *, const char *),
 		in_gap_prev = in_gap;
 		in_gap = (nrequests == 0);
 
-		if (!json && in_gap_prev && !in_gap) {
-			malloc_cprintf(write_cb, cbopaque,
+		if (in_gap_prev && !in_gap) {
+			emitter_table_printf(emitter,
 			    "                     ---\n");
 		}
 
 		CTL_M2_GET("arenas.lextent.0.size", j, &lextent_size, size_t);
 		CTL_M2_M4_GET("stats.arenas.0.lextents.0.curlextents", i, j,
 		    &curlextents, size_t);
-		if (json) {
-			malloc_cprintf(write_cb, cbopaque,
-			    "\t\t\t\t\t{\n"
-			    "\t\t\t\t\t\t\"curlextents\": %zu\n"
-			    "\t\t\t\t\t}%s\n",
-			    curlextents,
-			    (j + 1 < nlextents) ? "," : "");
-		} else if (!in_gap) {
-			malloc_cprintf(write_cb, cbopaque,
-			    "%20zu %3u %12zu %12"FMTu64" %12"FMTu64
-			    " %12"FMTu64" %12zu\n",
-			    lextent_size, nbins + j,
-			    curlextents * lextent_size, nmalloc, ndalloc,
-			    nrequests, curlextents);
+
+		emitter_json_arr_obj_begin(emitter);
+		emitter_json_kv(emitter, "curlextents", emitter_type_size,
+		    &curlextents);
+		emitter_json_arr_obj_end(emitter);
+
+		col_size.size_val = lextent_size;
+		col_ind.unsigned_val = nbins + j;
+		col_allocated.size_val = curlextents * lextent_size;
+		col_nmalloc.uint64_val = nmalloc;
+		col_ndalloc.uint64_val = ndalloc;
+		col_nrequests.uint64_val = nrequests;
+		col_curlextents.size_val = curlextents;
+
+		if (!in_gap) {
+			emitter_table_row(emitter, &row);
 		}
 	}
-	if (json) {
-		malloc_cprintf(write_cb, cbopaque,
-		    "\t\t\t\t]\n");
-	} else {
-		if (in_gap) {
-			malloc_cprintf(write_cb, cbopaque,
-			    "                     ---\n");
-		}
+	emitter_json_arr_end(emitter); /* Close "lextents". */
+	if (in_gap) {
+		emitter_table_printf(emitter, "                     ---\n");
 	}
 }
 
@@ -513,11 +536,6 @@ stats_arena_print(emitter_t *emitter, unsigned i, bool bins, bool large,
 	size_t tcache_bytes;
 	uint64_t uptime;
 
-	/* These should be removed once the emitter conversion is done. */
-	void (*write_cb)(void *, const char *) = emitter->write_cb;
-	void *cbopaque = emitter->cbopaque;
-	bool json = (emitter->output == emitter_output_json);
-
 	CTL_GET("arenas.page", &page, size_t);
 
 	CTL_M2_GET("stats.arenas.0.nthreads", i, &nthreads, unsigned);
@@ -799,17 +817,8 @@ stats_arena_print(emitter_t *emitter, unsigned i, bool bins, bool large,
 	if (bins) {
 		stats_arena_bins_print(emitter, mutex, i);
 	}
-
-	/* Emitter conversion point. */
-	if (json) {
-		if (large) {
-			malloc_cprintf(write_cb, cbopaque, ",\n");
-		} else {
-			malloc_cprintf(write_cb, cbopaque, "\n");
-		}
-	}
 	if (large) {
-		stats_arena_lextents_print(write_cb, cbopaque, json, i);
+		stats_arena_lextents_print(emitter, i);
 	}
 }