diff --git a/src/lib/editor/extensions/blockFontSize.ts b/src/lib/editor/extensions/blockFontSize.ts
index 555ec36..c92942a 100644
--- a/src/lib/editor/extensions/blockFontSize.ts
+++ b/src/lib/editor/extensions/blockFontSize.ts
@@ -47,12 +47,11 @@ export const BlockFontSize = Extension.create({
             renderHTML: (attributes: Record<string, unknown>) => {
               if (!attributes.fontFamily) return {};
               const family = String(attributes.fontFamily);
-              // Single spacing is this family's natural line height. An explicit line
-              // spacing already scales by it (lineHeight.ts), so it wins outright.
-              const lh = attributes.lineHeight ? '' : `; line-height: ${singleLineHeight(family)}`;
+              // Single spacing is this family's natural line height; the paragraph's own
+              // spacing factor multiplies it (editor.css).
               return {
                 'data-block-font-family': family,
-                style: `font-family: ${cssFontFamily(family)}${lh}`,
+                style: `font-family: ${cssFontFamily(family)}; --natural-line: ${singleLineHeight(family)}`,
               };
             },
           },
diff --git a/src/lib/editor/extensions/lineHeight.ts b/src/lib/editor/extensions/lineHeight.ts
index 33c01b4..b35d38a 100644
--- a/src/lib/editor/extensions/lineHeight.ts
+++ b/src/lib/editor/extensions/lineHeight.ts
@@ -1,5 +1,8 @@
 import { Extension } from '@tiptap/core';
-import { singleLineHeight } from '../../styles/styleSheet';
+
+// A line spacing is proportional to the font's natural line height, not to the font
+// size like CSS unitless line-height. The factor rides as a variable editor.css
+// multiplies by the block's own natural line height (blockFontSize.ts).
 
 declare module '@tiptap/core' {
   interface Commands<ReturnType> {
@@ -28,17 +31,14 @@ export const LineHeight = Extension.create({
             default: null,
             parseHTML: (element: HTMLElement) =>
               element.getAttribute('data-line-height') || null,
-            // A proportional spacing multiplies the font's natural line height, CSS the
-            // font size — so it is scaled by the paragraph mark's family (blockFontSize).
+            // The factor alone: editor.css multiplies it by the block's font's natural
+            // line height, which is what a proportional spacing is proportional to.
             renderHTML: (attributes: Record<string, unknown>) => {
               if (!attributes.lineHeight) return {};
               const raw = String(attributes.lineHeight);
-              const num = parseFloat(raw);
-              const family = attributes.fontFamily ? String(attributes.fontFamily) : undefined;
-              const rendered = isNaN(num) ? raw : `${Math.round(num * singleLineHeight(family) * 1000) / 1000}`;
               return {
                 'data-line-height': raw,
-                style: `line-height: ${rendered}`,
+                style: `--line-factor: ${raw}`,
               };
             },
           },
diff --git a/src/lib/export/docx.ts b/src/lib/export/docx.ts
index 8af465e..5b21bcb 100644
--- a/src/lib/export/docx.ts
+++ b/src/lib/export/docx.ts
@@ -941,6 +941,7 @@ function paragraphStyleOf(style: Style): IParagraphStyleOptions {
   // The registry holds the on-screen family; the file declares its metric twin.
   if (t.fontFamily) run.font = twinFontName(t.fontFamily);
   if (t.fontSizePt != null) run.size = Math.round(t.fontSizePt * 2);
+  if (t.letterSpacingPt) run.characterSpacing = Math.round(t.letterSpacingPt * 20);
   if (t.bold != null) run.bold = t.bold;
   if (t.italic != null) run.italics = t.italic;
   if (t.underline) run.underline = {};
@@ -971,6 +972,7 @@ function characterStyleOf(style: Style): ICharacterStyleOptions {
   const run: Writable<IRunStylePropertiesOptions> = {};
   if (t.fontFamily) run.font = t.fontFamily === 'Liberation Serif' ? DOC_FONT : t.fontFamily;
   if (t.fontSizePt != null) run.size = Math.round(t.fontSizePt * 2);
+  if (t.letterSpacingPt) run.characterSpacing = Math.round(t.letterSpacingPt * 20);
   if (t.bold != null) run.bold = t.bold;
   if (t.italic != null) run.italics = t.italic;
   if (t.underline) run.underline = {};
diff --git a/src/lib/export/odt.ts b/src/lib/export/odt.ts
index 5d9acc3..6ef2851 100644
--- a/src/lib/export/odt.ts
+++ b/src/lib/export/odt.ts
@@ -1153,6 +1153,7 @@ function ownStyleAttrs(style: { para: Record<string, unknown>; text: Record<stri
     text['style:font-size-asian'] = size;
     text['style:font-size-complex'] = size;
   }
+  if (t.letterSpacingPt) text['fo:letter-spacing'] = `${t.letterSpacingPt}pt`;
   if (t.bold != null) text['fo:font-weight'] = t.bold ? 'bold' : 'normal';
   if (t.italic != null) text['fo:font-style'] = t.italic ? 'italic' : 'normal';
   if (t.underline) text['style:text-underline-style'] = 'solid';
diff --git a/src/lib/import/docx.ts b/src/lib/import/docx.ts
index 4abf98b..d062162 100644
--- a/src/lib/import/docx.ts
+++ b/src/lib/import/docx.ts
@@ -618,6 +618,7 @@ function runTextProps(run: RunProps): TextProps {
   if (run.font) out.fontFamily = run.font === 'Times New Roman' ? 'Liberation Serif'
     : run.font === 'Arial' ? 'Liberation Sans' : run.font;
   if (run.sizeHalfPt != null) out.fontSizePt = Math.round((run.sizeHalfPt / 2) * 10) / 10;
+  if (run.spacingTwip) out.letterSpacingPt = Math.round((run.spacingTwip / 20) * 100) / 100;
   if (run.bold != null) out.bold = run.bold;
   if (run.italic != null) out.italic = run.italic;
   if (run.underline != null) out.underline = run.underline;
diff --git a/src/lib/import/docxStyles.ts b/src/lib/import/docxStyles.ts
index d5abdd7..f75b734 100644
--- a/src/lib/import/docxStyles.ts
+++ b/src/lib/import/docxStyles.ts
@@ -24,6 +24,7 @@ export type RunProps = {
   vertAlign?: 'superscript' | 'subscript';
   color?: string; // raw w:val hex (no #) or 'auto'
   sizeHalfPt?: number; // w:sz (half-points)
+  spacingTwip?: number; // w:spacing (character spacing, twentieths of a point)
   font?: string; // explicit w:rFonts w:ascii/hAnsi
   fontTheme?: 'minor' | 'major'; // w:rFonts w:asciiTheme/hAnsiTheme → theme1.xml font
   highlightFill?: string; // run-level w:shd w:fill (text highlight)
@@ -82,6 +83,7 @@ export function parseRunProps(rPr: Element | null | undefined): RunProps {
       }
       case 'color': { const v = wVal(child); if (v) p.color = v; break; }
       case 'sz': { const n = parseInt(wVal(child) ?? '', 10); if (Number.isFinite(n)) p.sizeHalfPt = n; break; }
+      case 'spacing': { const n = parseInt(wVal(child) ?? '', 10); if (Number.isFinite(n)) p.spacingTwip = n; break; }
       case 'rFonts': {
         const f = child.getAttributeNS(W, 'ascii') ?? child.getAttributeNS(W, 'hAnsi');
         if (f) { p.font = f; break; }
diff --git a/src/lib/import/odt.ts b/src/lib/import/odt.ts
index 647b1a6..b1b9336 100644
--- a/src/lib/import/odt.ts
+++ b/src/lib/import/odt.ts
@@ -775,6 +775,8 @@ function textPropsFromOdf(props: PropMap, resolver: StyleResolver): TextProps {
   if (family) out.fontFamily = screenFontName(family);
   const size = lengthToPt(props['fo:font-size']);
   if (size != null) out.fontSizePt = Math.round(size * 10) / 10;
+  const spacing = lengthToPt(props['fo:letter-spacing']);
+  if (spacing) out.letterSpacingPt = Math.round(spacing * 100) / 100;
   const weight = props['fo:font-weight'];
   if (weight) out.bold = weight === 'bold' || parseInt(weight, 10) >= 600;
   const style = props['fo:font-style'];
diff --git a/src/lib/styles/styleSheet.ts b/src/lib/styles/styleSheet.ts
index 58431bf..fa081ba 100644
--- a/src/lib/styles/styleSheet.ts
+++ b/src/lib/styles/styleSheet.ts
@@ -20,6 +20,7 @@ export type ParaProps = {
 export type TextProps = {
   fontFamily?: string;
   fontSizePt?: number;
+  letterSpacingPt?: number; // character spacing (Word's w:spacing, ODF fo:letter-spacing)
   bold?: boolean;
   italic?: boolean;
   underline?: boolean;
@@ -200,7 +201,7 @@ export function cssFontFamily(name: string): string {
 // Single spacing is the font's *natural* line height, so it differs per family.
 // Liberation Serif's 1.15 is the default (editor.css); only the bundled families that
 // deviate are listed, measured against LibreOffice at 12pt.
-export const DEFAULT_SINGLE_LINE_HEIGHT = 1.15;
+const DEFAULT_SINGLE_LINE_HEIGHT = 1.15;
 const SINGLE_LINE_HEIGHT: Record<string, number> = {
   Calibri: 1.2208,
   'Calibri Light': 1.2208,
@@ -215,16 +216,18 @@ export function singleLineHeight(fontFamily?: string): number {
   return (fontFamily && SINGLE_LINE_HEIGHT[fontFamily]) || DEFAULT_SINGLE_LINE_HEIGHT;
 }
 
-// The text half of a rule, shared with the table-style family (tableStyles.ts).
-export function textDeclarations(t: TextProps): string[] {
+// The text half of a rule, shared with the table-style family (tableStyles.ts). A block
+// takes the family's natural line height as the variable editor.css multiplies by the
+// paragraph's spacing factor; a run box sets its line height outright.
+export function textDeclarations(t: TextProps, asBlock = false): string[] {
   const out: string[] = [];
   if (t.fontFamily) {
     out.push(`font-family: ${cssFontFamily(t.fontFamily)}`);
     const lh = SINGLE_LINE_HEIGHT[t.fontFamily];
-    // An explicit line spacing is emitted after this and wins.
-    if (lh) out.push(`line-height: ${lh}`);
+    if (lh) out.push(`${asBlock ? '--natural-line' : 'line-height'}: ${lh}`);
   }
   if (t.fontSizePt != null) out.push(`font-size: ${t.fontSizePt}pt`);
+  if (t.letterSpacingPt) out.push(`letter-spacing: ${t.letterSpacingPt}pt`);
   if (t.bold != null) out.push(`font-weight: ${t.bold ? 700 : 400}`);
   if (t.italic != null) out.push(`font-style: ${t.italic ? 'italic' : 'normal'}`);
   if (t.underline || t.strike) {
@@ -236,13 +239,9 @@ export function textDeclarations(t: TextProps): string[] {
 
 function declarations(r: ResolvedStyle): string[] {
   const { para: p } = r;
-  const out = textDeclarations(r.text);
+  const out = textDeclarations(r.text, true);
   if (p.textAlign) out.push(`text-align: ${p.textAlign}`);
-  if (p.lineHeight) {
-    const n = parseFloat(p.lineHeight);
-    const scaled = Math.round(n * singleLineHeight(r.text.fontFamily) * 1000) / 1000;
-    out.push(`line-height: ${isNaN(n) ? p.lineHeight : scaled}`);
-  }
+  if (p.lineHeight) out.push(`--line-factor: ${p.lineHeight}`);
   if (p.spaceBefore != null) out.push(`margin-top: ${p.spaceBefore}pt`);
   if (p.spaceAfter != null) out.push(`margin-bottom: ${p.spaceAfter}pt`);
   if (p.indent != null) out.push(`margin-left: ${p.indent}cm`);
diff --git a/src/styles/editor.css b/src/styles/editor.css
index bdd53ac..ea33ed1 100644
--- a/src/styles/editor.css
+++ b/src/styles/editor.css
@@ -49,9 +49,11 @@
   font-family: var(--font-serif);
   /* 12pt matches odf-kit's Standard style and the toolbar's declared default. */
   font-size: 12pt;
-  /* ODF/LibreOffice "single" spacing = the font's natural line height
-     (Liberation Serif ≈ 1.15× em), NOT 1.0× the font size like CSS unitless 1.
-     Keep this in sync with LINE_HEIGHT_RATIO in lineHeight.ts. */
+  /* "Single" spacing is the font's natural line height (Liberation Serif ≈ 1.15× em),
+     not CSS unitless 1. A paragraph's line spacing multiplies that, so the two ride as
+     separate variables and the block rule below is the one place they meet. */
+  --natural-line: 1.15;
+  --line-factor: 1;
   line-height: 1.15;
   color: var(--color-page-text);
 
@@ -392,7 +394,13 @@
      (styles/styleSheet.ts → the #document-styles element Editor.svelte writes). */
   font: inherit;
   margin: 0;
-  line-height: 1.15;
+}
+
+/* The line box: the paragraph's spacing factor times its font's natural line height.
+   Either half may come from the style rule or, nearer, from the block's own attrs
+   (lineHeight.ts / blockFontSize.ts) — multiplying them here is what keeps both. */
+.paper .tiptap :is(p, h1, h2, h3, h4, h5, li) {
+  line-height: calc(var(--line-factor) * var(--natural-line));
 }
 
 .paper .tiptap ul,