diff --git a/crates/ui-egui/src/backstage.rs b/crates/ui-egui/src/backstage.rs
index ead3f81c4..3ceef246f 100644
--- a/crates/ui-egui/src/backstage.rs
+++ b/crates/ui-egui/src/backstage.rs
@@ -1001,13 +1001,14 @@ fn options(app: &mut SheetApp, ui: &mut Ui) {
         app.run_or_alert("formulas.calculationOptions", json!({"iterative": iterative}));
     }
     // Maximum Iterations and Maximum Change apply only while iteration is on, as in Excel.
-    ui.add_enabled_ui(calc.iterative, |ui| {
+    ui.add_enabled_ui(iterative, |ui| {
         ui.horizontal(|ui| {
             ui.add_space(24.0);
             egui::Grid::new("backstage_options_iteration").num_columns(2).spacing(vec2(12.0, 6.0)).show(ui, |ui| {
                 ui.label(lang.tr("Maximum Iterations:"));
                 let id = ui.make_persistent_id("backstage_max_iterations");
-                if let Some(text) = crate::widgets::committed_text(ui, id, &calc.max_iterations.to_string(), Some(80.0)) {
+                // Text left in the field when iteration is switched off (it loses focus) is dropped.
+                if let Some(text) = crate::widgets::committed_text(ui, id, &calc.max_iterations.to_string(), Some(80.0)).filter(|_| iterative) {
                     match parse_max_iterations(&text) {
                         Some(n) if n != calc.max_iterations => {
                             app.run_or_alert("formulas.calculationOptions", json!({"maxIterations": n}));
@@ -1019,8 +1020,8 @@ fn options(app: &mut SheetApp, ui: &mut Ui) {
                 ui.end_row();
                 ui.label(lang.tr("Maximum Change:"));
                 let id = ui.make_persistent_id("backstage_max_change");
-                if let Some(text) = crate::widgets::committed_text(ui, id, &calc.max_change.to_string(), Some(80.0)) {
-                    match parse_max_change(&text) {
+                if let Some(text) = crate::widgets::committed_text(ui, id, &calc.max_change.to_string(), Some(80.0)).filter(|_| iterative) {
+                    match parse_max_change(&text, lang.formula_locale()) {
                         Some(d) if d != calc.max_change => {
                             app.run_or_alert("formulas.calculationOptions", json!({"maxChange": d}));
                         }
@@ -1051,9 +1052,10 @@ fn parse_max_iterations(text: &str) -> Option<u32> {
     (1..=gridcraft_engine::model::CalcSettings::MAX_ITERATIONS).contains(&n).then_some(n)
 }
 
-/// Maximum Change as typed: a finite number of 0 or more, or `None`.
-fn parse_max_change(text: &str) -> Option<f64> {
-    let d = text.trim().parse::<f64>().ok()?;
+/// Maximum Change as typed: a finite number of 0 or more, or `None`. The interface's decimal
+/// separator is accepted as well as a dot.
+fn parse_max_change(text: &str, locale: gridcraft_engine::formula::FormulaLocale) -> Option<f64> {
+    let d = text.trim().replace(locale.decimal_separator(), ".").parse::<f64>().ok()?;
     (d.is_finite() && d >= 0.0).then_some(d)
 }
 
diff --git a/crates/ui-egui/tests/it/file_menu.rs b/crates/ui-egui/tests/it/file_menu.rs
index 916185665..6b4cbc6a7 100644
--- a/crates/ui-egui/tests/it/file_menu.rs
+++ b/crates/ui-egui/tests/it/file_menu.rs
@@ -415,6 +415,34 @@ fn options_sets_maximum_iterations_and_change_only_while_iteration_is_on() {
     assert_eq!(calc(&h).max_change, 0.01);
     let change = field(&h, "Maximum Change:");
     assert_eq!(h.get_all_by_role(Role::TextInput).find(|n| n.rect() == change).unwrap().value().as_deref(), Some("0.01"));
+
+    // A value typed but not confirmed with Enter is dropped when the checkbox switches iteration off.
+    let iterations = field(&h, "Maximum Iterations:");
+    h.input_mut().events.push(egui::Event::PointerMoved(iterations.center()));
+    h.run_steps(1);
+    h.get_all_by_role(Role::TextInput).find(|n| n.rect() == iterations).unwrap().click();
+    h.run_steps(2);
+    h.key_press_modifiers(egui::Modifiers::COMMAND, egui::Key::A);
+    h.input_mut().events.push(egui::Event::Text("777".into()));
+    h.run_steps(2);
+    h.get_by_role_and_label(Role::CheckBox, "Enable iterative calculation").click();
+    h.run_steps(3);
+    assert!(!calc(&h).iterative);
+    assert_eq!(calc(&h).max_iterations, 32767, "an unconfirmed entry is not committed once iteration is off");
+    assert!(h.state().message.is_none());
+
+    // Spanish accepts a decimal comma in Maximum Change, and still a dot.
+    h.get_by_role_and_label(Role::CheckBox, "Enable iterative calculation").click();
+    h.run_steps(3);
+    h.state_mut().run("app.language.set", serde_json::json!({"language": Language::Es.code()})).unwrap();
+    h.state_mut().run("file.options", serde_json::json!({})).unwrap();
+    h.run_steps(3);
+    let change = field(&h, "Cambio máximo:");
+    retype(&mut h, change, "0,02");
+    assert_eq!(calc(&h).max_change, 0.02);
+    retype(&mut h, change, "0.5");
+    assert_eq!(calc(&h).max_change, 0.5);
+    assert!(h.state().message.is_none());
 }
 
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