diff --git a/website/src/features/toolboxes/modules/CalculatorModule.jsx b/website/src/features/toolboxes/modules/CalculatorModule.jsx
index 9149e8a..b506ca7 100644
--- a/website/src/features/toolboxes/modules/CalculatorModule.jsx
+++ b/website/src/features/toolboxes/modules/CalculatorModule.jsx
@@ -5,6 +5,8 @@ import { useInlineEdit } from "../../../hooks/useInlineEdit.js";
 import { moveItem, useGroupedReorder } from "../../../hooks/useGroupedReorder.js";
 import { TextExchangeActions } from "./TextExchangeActions.jsx";
 
+const DISPLAY_NUMBER_FORMATTER = new Intl.NumberFormat("fr-FR", { maximumFractionDigits: 6 });
+
 function calculateExpression(expression) {
   const normalized = String(expression || "").replaceAll(",", ".").trim();
   if (!normalized || !/^[\d\s+\-*/().]+$/.test(normalized)) return null;
@@ -24,13 +26,13 @@ function formatResult(value) {
 
 function formatDisplayResult(value) {
   if (!Number.isFinite(value)) return "";
-  return new Intl.NumberFormat("fr-FR", { maximumFractionDigits: 6 }).format(Number.parseFloat(value.toFixed(6)));
+  return DISPLAY_NUMBER_FORMATTER.format(Number.parseFloat(value.toFixed(6)));
 }
 
 function getResultLengthClass(value) {
   const length = formatResult(value).replace(/[^\d]/g, "").length;
-  if (length >= 16) return "is-compact";
-  if (length >= 12) return "is-long";
+  if (length >= 13) return "is-compact";
+  if (length >= 9) return "is-long";
   return "";
 }
 
@@ -47,6 +49,21 @@ function getEntriesInTreeOrder(entries, parentId = "") {
   return getChildren(entries, parentId).flatMap((entry) => [entry, ...getEntriesInTreeOrder(entries, entry.id)]);
 }
 
+function FormattedCalculatorNumber({ value }) {
+  if (!Number.isFinite(value)) return "-";
+  let integerGroupIndex = 0;
+  const normalized = Number.parseFloat(value.toFixed(6));
+  return DISPLAY_NUMBER_FORMATTER.formatToParts(normalized).map((part, index) => {
+    if (part.type === "integer") {
+      const className = `calculator-number-group ${integerGroupIndex % 2 ? "is-muted" : "is-strong"}`;
+      integerGroupIndex += 1;
+      return <span className={className} key={`${part.type}-${index}`}>{part.value}</span>;
+    }
+    if (part.type === "group") return <span className="calculator-number-separator" key={`${part.type}-${index}`}>{part.value}</span>;
+    return <span key={`${part.type}-${index}`}>{part.value}</span>;
+  });
+}
+
 export function CalculatorModule({ toolboxId, moduleId, context, editing }) {
   const data = context.normalizeCalculatorData(context.getModuleData(toolboxId, moduleId, { entries: [] }));
   const textContent = context.moduleText?.calculator || {};
@@ -165,7 +182,9 @@ export function CalculatorModule({ toolboxId, moduleId, context, editing }) {
           </label>
           <div className={`calculator-result ${result == null ? "" : getResultLengthClass(result)}`} aria-live="polite">
             <span>{textContent.resultLabel || "Résultat"}</span>
-            <strong>{result == null ? "-" : formatDisplayResult(result)}</strong>
+            <strong aria-label={result == null ? "-" : formatDisplayResult(result)}>
+              <FormattedCalculatorNumber value={result} />
+            </strong>
           </div>
           <label>
             <span>{textContent.labelLabel || "Libellé"}</span>
@@ -245,14 +264,18 @@ function CalculatorEntries({ entries, parentId, getScopedParentId, activeParentI
             {entry.id === editingId ? (
               <>
                 <span className="tool-split-entry-value is-readonly" title={textContent.readonlyValueTitle || "Quantité non modifiable"}>
-                  <strong>{formatDisplayResult(entry.value)}</strong>
+                  <strong className={getResultLengthClass(entry.value)} aria-label={formatDisplayResult(entry.value)}>
+                    <FormattedCalculatorNumber value={entry.value} />
+                  </strong>
                 </span>
                 <EditableCalculatorLabel entry={entry} textContent={textContent} onRename={onRename} onDone={() => setEditingId("")} />
               </>
             ) : (
               <button className="tool-split-entry-summary" type="button" onClick={() => onUse(entry)} title={textContent.useEntryTitle || "Utiliser comme base"}>
                 <span>
-                  <strong>{formatDisplayResult(entry.value)}</strong>
+                  <strong className={getResultLengthClass(entry.value)} aria-label={formatDisplayResult(entry.value)}>
+                    <FormattedCalculatorNumber value={entry.value} />
+                  </strong>
                   {entry.label && <em>{entry.label}</em>}
                 </span>
               </button>
diff --git a/website/src/styles/_toolboxes.scss b/website/src/styles/_toolboxes.scss
index 50dca8c..be08932 100644
--- a/website/src/styles/_toolboxes.scss
+++ b/website/src/styles/_toolboxes.scss
@@ -5216,13 +5216,24 @@ button.combo-input-token.combo-value-grab .ui-icon {
 .calculator-entry .tool-split-entry-summary strong,
 .calculator-entry .tool-split-entry-value strong {
   min-width: 0;
-  overflow: hidden;
-  text-overflow: ellipsis;
+  overflow: visible;
+  font-variant-numeric: tabular-nums;
   white-space: nowrap;
 }
 
 .calculator-entry .tool-split-entry-summary strong {
-  flex: 0 1 auto;
+  flex: 0 0 auto;
+  font-size: var(--font-size-sm);
+}
+
+.calculator-entry .tool-split-entry-summary strong.is-long,
+.calculator-entry .tool-split-entry-value strong.is-long {
+  font-size: var(--font-size-xs);
+}
+
+.calculator-entry .tool-split-entry-summary strong.is-compact,
+.calculator-entry .tool-split-entry-value strong.is-compact {
+  font-size: 0.68rem;
 }
 
 .calculator-entry .tool-split-entry-summary em {
@@ -5235,6 +5246,20 @@ button.combo-input-token.combo-value-grab .ui-icon {
   white-space: nowrap;
 }
 
+.calculator-number-group {
+  color: var(--color-text-primary);
+}
+
+.calculator-number-group.is-muted,
+.calculator-number-separator {
+  color: rgba(180, 189, 211, 0.68);
+}
+
+.calculator-number-separator {
+  display: inline-block;
+  min-width: 0.24em;
+}
+
 .calculator-form label span,
 .calculator-result span,
 .tool-split-root-button {
@@ -5258,23 +5283,23 @@ button.combo-input-token.combo-value-grab .ui-icon {
   display: block;
   min-width: 0;
   max-width: 100%;
-  overflow: hidden;
+  overflow: visible;
   color: var(--color-text-primary);
   font-size: clamp(1.55rem, 3vw, 2.15rem);
+  font-variant-numeric: tabular-nums;
   font-weight: 900;
   line-height: 0.95;
   text-align: right;
-  text-overflow: ellipsis;
   white-space: nowrap;
 }
 
 .calculator-result.is-long strong {
-  font-size: 1.55rem;
+  font-size: 1.18rem;
   line-height: 1;
 }
 
 .calculator-result.is-compact strong {
-  font-size: 1.25rem;
+  font-size: 0.92rem;
   line-height: 1.05;
 }