diff -ruN a/config.def.h b/config.def.h
--- a/config.def.h	2026-05-20 11:57:26.722347891 +0200
+++ b/config.def.h	2026-05-20 11:57:26.726347974 +0200
@@ -3,3 +3,8 @@
 /* progress bar glyphs (ASCII default) */
 static const char *const BAR_FILL  = ">";
 static const char *const BAR_EMPTY = "-";
+
+/* log location is ~/.config/ttym/ttym.log (honours $XDG_CONFIG_HOME).
+ * One-shot migration: ~/.config/timer/ -> ~/.config/ttym/ if the new
+ * directory doesn't already exist; legacy log file inside is renamed.
+ */
diff -ruN a/ttym.c b/ttym.c
--- a/ttym.c	2026-05-20 11:57:26.722347891 +0200
+++ b/ttym.c	2026-05-20 11:57:26.726347974 +0200
@@ -12,6 +12,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/ioctl.h>
+#include <sys/stat.h>
 #include <termios.h>
 #include <time.h>
 #include <unistd.h>
@@ -23,6 +24,7 @@
 typedef struct {
 	int quiet;            /* -q: suppress completion bell */
 	int silent;           /* -s: no bell, no extras */
+	char comment[512];    /* -c TEXT: logged with each entry */
 } Config;
 
 static struct termios oldtios;
@@ -226,6 +228,367 @@
 	fflush(stdout);
 }
 
+/* ===== log (TSV: ts<TAB>seconds<TAB>comment) ===== */
+
+static int
+build_config_path(char *buf, size_t bufsz, const char *suffix)
+{
+	const char *home = getenv("HOME");
+	const char *xdg  = getenv("XDG_CONFIG_HOME");
+	if (xdg && *xdg)        snprintf(buf, bufsz, "%s/ttym/%s", xdg, suffix);
+	else if (home && *home) snprintf(buf, bufsz, "%s/.config/ttym/%s", home, suffix);
+	else return -1;
+	return 0;
+}
+
+static void
+migrate_legacy_dir(void)
+{
+	const char *home = getenv("HOME");
+	const char *xdg  = getenv("XDG_CONFIG_HOME");
+	char base[512];
+	if (xdg && *xdg)        snprintf(base, sizeof(base), "%s", xdg);
+	else if (home && *home) snprintf(base, sizeof(base), "%s/.config", home);
+	else return;
+	char old_dir[600], new_dir[600];
+	snprintf(old_dir, sizeof(old_dir), "%s/timer", base);
+	snprintf(new_dir, sizeof(new_dir), "%s/ttym",  base);
+	struct stat sb;
+	if (stat(new_dir, &sb) == 0) return;
+	if (stat(old_dir, &sb) != 0 || !S_ISDIR(sb.st_mode)) return;
+	if (rename(old_dir, new_dir) != 0) return;
+	char old_log[700], new_log[700];
+	snprintf(old_log, sizeof(old_log), "%s/timer.log", new_dir);
+	snprintf(new_log, sizeof(new_log), "%s/ttym.log",  new_dir);
+	if (stat(old_log, &sb) == 0) rename(old_log, new_log);
+}
+
+static int
+mkdir_p(const char *path, mode_t mode)
+{
+	char buf[1024];
+	snprintf(buf, sizeof(buf), "%s", path);
+	for (char *p = buf + 1; *p; p++) {
+		if (*p == '/') {
+			*p = '\0';
+			if (mkdir(buf, mode) != 0 && errno != EEXIST) return -1;
+			*p = '/';
+		}
+	}
+	if (mkdir(buf, mode) != 0 && errno != EEXIST) return -1;
+	return 0;
+}
+
+static void
+iso_local(char *buf, size_t bufsz)
+{
+	time_t t = time(NULL);
+	struct tm tm;
+	localtime_r(&t, &tm);
+	strftime(buf, bufsz, "%Y-%m-%d %H:%M:%S", &tm);
+}
+
+static void
+sanitize_field(char *s)
+{
+	for (; *s; s++)
+		if (*s == '\t' || *s == '\n' || *s == '\r') *s = ' ';
+}
+
+static int
+is_old_format(const char *line)
+{
+	return strlen(line) >= 11 && line[10] == 'T';
+}
+
+static void
+migrate_line(const char *line, char *out, size_t outsz)
+{
+	if (strlen(line) < 19) { snprintf(out, outsz, "%s", line); return; }
+	char date[11], tpart[9];
+	memcpy(date, line, 10); date[10] = '\0';
+	memcpy(tpart, line + 11, 8); tpart[8] = '\0';
+	const char *tab = strchr(line, '\t');
+	if (!tab) { snprintf(out, outsz, "%s %s\n", date, tpart); return; }
+	snprintf(out, outsz, "%s %s%s", date, tpart, tab);
+}
+
+static void
+migrate_log_if_needed(const char *path)
+{
+	FILE *f = fopen(path, "r");
+	if (!f) return;
+	char probe[2048];
+	int needs = 0;
+	while (fgets(probe, sizeof(probe), f))
+		if (is_old_format(probe)) { needs = 1; break; }
+	if (!needs) { fclose(f); return; }
+	rewind(f);
+	char tmp[1024];
+	snprintf(tmp, sizeof(tmp), "%s.tmp", path);
+	FILE *out = fopen(tmp, "w");
+	if (!out) { fclose(f); return; }
+	char line[2048];
+	while (fgets(line, sizeof(line), f)) {
+		if (is_old_format(line)) {
+			char conv[2048];
+			migrate_line(line, conv, sizeof(conv));
+			fputs(conv, out);
+		} else fputs(line, out);
+	}
+	fclose(f);
+	fclose(out);
+	rename(tmp, path);
+}
+
+static void
+write_log(long duration_s, const char *comment)
+{
+	char path[512];
+	if (build_config_path(path, sizeof(path), "ttym.log") < 0) return;
+	char dir[512];
+	snprintf(dir, sizeof(dir), "%s", path);
+	char *slash = strrchr(dir, '/');
+	if (slash) { *slash = '\0'; mkdir_p(dir, 0700); }
+	migrate_log_if_needed(path);
+	int fd = open(path, O_WRONLY | O_CREAT | O_APPEND, 0600);
+	if (fd < 0) return;
+	char ts[32]; iso_local(ts, sizeof(ts));
+	char safe[512]; snprintf(safe, sizeof(safe), "%s", comment ? comment : "");
+	sanitize_field(safe);
+	char line[1024];
+	int n = snprintf(line, sizeof(line), "%s\t%ld\t%s\n", ts, duration_s, safe);
+	if (n > 0) { ssize_t w = write(fd, line, (size_t)n); (void)w; }
+	close(fd);
+}
+
+static int
+read_log_lines(char ***out_lines, size_t *out_n)
+{
+	char path[512];
+	if (build_config_path(path, sizeof(path), "ttym.log") < 0) return -1;
+	migrate_log_if_needed(path);
+	FILE *f = fopen(path, "r");
+	if (!f) { *out_lines = NULL; *out_n = 0; return 0; }
+	size_t cap = 64, n = 0;
+	char **lines = malloc(cap * sizeof(char *));
+	if (!lines) { fclose(f); return -1; }
+	char buf[2048];
+	while (fgets(buf, sizeof(buf), f)) {
+		size_t l = strlen(buf);
+		if (l && buf[l-1] == '\n') buf[l-1] = '\0';
+		if (!*buf) continue;
+		if (n >= cap) {
+			cap *= 2;
+			char **nl = realloc(lines, cap * sizeof(char *));
+			if (!nl) break;
+			lines = nl;
+		}
+		lines[n++] = strdup(buf);
+	}
+	fclose(f);
+	*out_lines = lines;
+	*out_n = n;
+	return 0;
+}
+
+static void
+free_lines(char **lines, size_t n)
+{
+	if (!lines) return;
+	for (size_t i = 0; i < n; i++) free(lines[i]);
+	free(lines);
+}
+
+static int
+split_log_line(char *line, char **ts, long *secs, char **comment)
+{
+	char *t1 = strchr(line, '\t'); if (!t1) return -1;
+	*t1 = '\0';
+	char *t2 = strchr(t1 + 1, '\t'); if (!t2) return -1;
+	*t2 = '\0';
+	char *end;
+	long v = strtol(t1 + 1, &end, 10);
+	if (end == t1 + 1) return -1;
+	*ts = line; *secs = v; *comment = t2 + 1;
+	return 0;
+}
+
+static void
+fmt_long(long s, char *buf, size_t bufsz)
+{
+	if (s < 0) s = 0;
+	long d = s / 86400; s %= 86400;
+	long h = s / 3600;  s %= 3600;
+	long m = s / 60;
+	long sec = s % 60;
+	snprintf(buf, bufsz, "%02ld %02ld:%02ld:%02ld", d, h, m, sec);
+}
+
+static int
+cmd_read(int argc, char **argv)
+{
+	int n_tail = 0, raw = 0;
+	for (int i = 0; i < argc; i++) {
+		if (!strcmp(argv[i], "-n") && i + 1 < argc) {
+			n_tail = atoi(argv[++i]);
+			if (n_tail < 0) n_tail = 0;
+		} else if (!strcmp(argv[i], "--raw")) {
+			raw = 1;
+		} else {
+			fprintf(stderr, "timer -r: unknown arg: %s\n", argv[i]);
+			return 1;
+		}
+	}
+	char **lines = NULL; size_t n = 0;
+	if (read_log_lines(&lines, &n) < 0) return 1;
+	if (n == 0) { free_lines(lines, n); return 0; }
+	size_t start = 0;
+	if (n_tail > 0 && (size_t)n_tail < n) start = n - n_tail;
+	if (raw) {
+		for (size_t i = start; i < n; i++) puts(lines[i]);
+	} else {
+		printf("%-19s  %-11s  %s\n", "TIMESTAMP", "DURATION", "COMMENT");
+		for (size_t i = start; i < n; i++) {
+			char *copy = strdup(lines[i]);
+			char *ts, *cmt; long secs;
+			if (split_log_line(copy, &ts, &secs, &cmt) == 0) {
+				char dur[32];
+				fmt_long(secs, dur, sizeof(dur));
+				printf("%-19s  %-11s  %s\n", ts, dur, cmt);
+			} else {
+				puts(lines[i]);
+			}
+			free(copy);
+		}
+	}
+	free_lines(lines, n);
+	return 0;
+}
+
+static int
+parse_log_ts(const char *ts, struct tm *out)
+{
+	memset(out, 0, sizeof(*out));
+	if (sscanf(ts, "%d-%d-%d %d:%d:%d",
+	           &out->tm_year, &out->tm_mon, &out->tm_mday,
+	           &out->tm_hour, &out->tm_min, &out->tm_sec) != 6) return -1;
+	out->tm_year -= 1900;
+	out->tm_mon  -= 1;
+	out->tm_isdst = -1;
+	return 0;
+}
+
+typedef struct TagAcc {
+	char tag[128];
+	long secs;
+	long count;
+	struct TagAcc *next;
+} TagAcc;
+
+static void
+tag_add(TagAcc **head, const char *tag, long secs)
+{
+	for (TagAcc *a = *head; a; a = a->next)
+		if (!strcmp(a->tag, tag)) { a->secs += secs; a->count++; return; }
+	TagAcc *n = calloc(1, sizeof(*n));
+	if (!n) return;
+	snprintf(n->tag, sizeof(n->tag), "%s", tag);
+	n->secs = secs;
+	n->count = 1;
+	n->next = *head;
+	*head = n;
+}
+
+static void
+extract_tags(const char *comment, long secs, TagAcc **head)
+{
+	const char *p = comment;
+	int found = 0;
+	while (*p) {
+		int at_boundary = (p == comment) || isspace((unsigned char)*(p-1));
+		if (*p == '+' && at_boundary) {
+			const char *s = p + 1, *e = s;
+			while (*e && !isspace((unsigned char)*e)) e++;
+			if (e > s) {
+				char buf[128];
+				size_t len = (size_t)(e - s);
+				if (len >= sizeof(buf)) len = sizeof(buf) - 1;
+				memcpy(buf, s, len); buf[len] = '\0';
+				tag_add(head, buf, secs);
+				found = 1;
+			}
+			p = e;
+		} else p++;
+	}
+	if (!found) tag_add(head, "(untagged)", secs);
+}
+
+static int
+cmd_stats(int argc, char **argv)
+{
+	const char *period = (argc > 0) ? argv[0] : "today";
+	time_t now = time(NULL);
+	struct tm now_tm; localtime_r(&now, &now_tm);
+	time_t cutoff = 0;
+	if      (!strcmp(period, "all"))   cutoff = 0;
+	else if (!strcmp(period, "today")) {
+		struct tm t = now_tm; t.tm_hour = t.tm_min = t.tm_sec = 0;
+		cutoff = mktime(&t);
+	} else if (!strcmp(period, "week")) {
+		struct tm t = now_tm; t.tm_hour = t.tm_min = t.tm_sec = 0;
+		int back = (t.tm_wday == 0) ? 6 : t.tm_wday - 1;
+		t.tm_mday -= back;
+		cutoff = mktime(&t);
+	} else if (!strcmp(period, "month")) {
+		struct tm t = now_tm; t.tm_hour = t.tm_min = t.tm_sec = 0; t.tm_mday = 1;
+		cutoff = mktime(&t);
+	} else {
+		fprintf(stderr, "stats: unknown period '%s' (today|week|month|all)\n", period);
+		return 1;
+	}
+	char **lines = NULL; size_t n = 0;
+	if (read_log_lines(&lines, &n) < 0) return 1;
+	long total = 0, count = 0;
+	TagAcc *tags = NULL;
+	for (size_t i = 0; i < n; i++) {
+		char *copy = strdup(lines[i]);
+		char *ts, *cmt; long secs;
+		if (split_log_line(copy, &ts, &secs, &cmt) != 0) { free(copy); continue; }
+		struct tm tm;
+		if (parse_log_ts(ts, &tm) != 0) { free(copy); continue; }
+		time_t entry = mktime(&tm);
+		if (cutoff && entry < cutoff) { free(copy); continue; }
+		total += secs; count++;
+		extract_tags(cmt, secs, &tags);
+		free(copy);
+	}
+	free_lines(lines, n);
+	char tot[32]; fmt_long(total, tot, sizeof(tot));
+	printf("\033[1m== timer stats: %s ==\033[0m\n", period);
+	printf("entries: %ld    total: %s\n\n", count, tot);
+	int tag_n = 0;
+	for (TagAcc *a = tags; a; a = a->next) tag_n++;
+	if (tag_n > 0) {
+		TagAcc **arr = malloc(tag_n * sizeof(*arr));
+		int i = 0;
+		for (TagAcc *a = tags; a; a = a->next) arr[i++] = a;
+		for (int x = 0; x < tag_n - 1; x++)
+			for (int y = x + 1; y < tag_n; y++)
+				if (arr[y]->secs > arr[x]->secs) {
+					TagAcc *t = arr[x]; arr[x] = arr[y]; arr[y] = t;
+				}
+		printf("%-24s  %-11s  %5s\n", "TAG", "DURATION", "COUNT");
+		for (int z = 0; z < tag_n; z++) {
+			char d[32]; fmt_long(arr[z]->secs, d, sizeof(d));
+			printf("%-24s  %-11s  %5ld\n", arr[z]->tag, d, arr[z]->count);
+		}
+		free(arr);
+	}
+	while (tags) { TagAcc *next = tags->next; free(tags); tags = next; }
+	return 0;
+}
+
 /* ===== usage =====
  * Patches MUST update this in lockstep with new flags so -h always
  * reflects the build.
@@ -238,9 +601,12 @@
 "usage:\n"
 "  timer [FLAGS] DURATION    countdown\n"
 "  timer [FLAGS]             stopwatch\n"
+"  timer -r [-n N] [--raw]                read log\n"
+"  timer --stats [today|week|month|all]   stats (default: today)\n"
 "\n"
 "DURATION:  25m | 90s | 2h | 1h30m | 01:30:00 | 25:00\n"
 "FLAGS:\n"
+"  -c TEXT         comment for log (+tag tokens are extracted)\n"
 "  -q              no sound\n"
 "  -s              silent\n"
 "  --              end of options\n"
@@ -378,6 +744,7 @@
 	}
 
 	(void)cfg;
+	write_log(elapsed_s, cfg->comment);
 	return user_quit ? 130 : 0;
 }
 
@@ -386,6 +753,13 @@
 int
 main(int argc, char **argv)
 {
+	migrate_legacy_dir();
+
+	if (argc >= 2 && !strcmp(argv[1], "-r"))
+		return cmd_read(argc - 2, argv + 2);
+	if (argc >= 2 && !strcmp(argv[1], "--stats"))
+		return cmd_stats(argc - 2, argv + 2);
+
 	Config cfg = {0};
 
 	/* Pre-strip long-form flags before getopt. Stop at "--". */
@@ -404,10 +778,11 @@
 	new_argv[new_argc] = NULL;
 
 	int opt;
-	while ((opt = getopt(new_argc, new_argv, "qsh")) != -1) {
+	while ((opt = getopt(new_argc, new_argv, "qsc:h")) != -1) {
 		switch (opt) {
 		case 'q': cfg.quiet  = 1; break;
 		case 's': cfg.silent = 1; break;
+		case 'c': snprintf(cfg.comment, sizeof(cfg.comment), "%s", optarg); break;
 		case 'h': usage(stdout); free(new_argv); return 0;
 		default:  usage(stderr); free(new_argv); return 1;
 		}