diff --git a/web/scripts/e2e-player.mjs b/web/scripts/e2e-player.mjs
index 5576a40..fb5faae 100644
--- a/web/scripts/e2e-player.mjs
+++ b/web/scripts/e2e-player.mjs
@@ -95,6 +95,22 @@ await page.screenshot({ path: `${SHOTS}/h1-auto.png` })
   await page.evaluate((t) => t ? document.documentElement.setAttribute('data-theme', t) : document.documentElement.removeAttribute('data-theme'), was)
 }
 
+// Volume: the speaker mutes and unmutes, the slider sets the level, and it is remembered.
+{
+  await controls()
+  const vs = () => page.evaluate(() => { const v = document.querySelector('.vp video'); return { muted: v.muted, volume: Math.round(v.volume * 100) / 100 } })
+  await page.getByRole('button', { name: 'Mute' }).click()
+  const a = await vs()
+  await page.getByRole('button', { name: 'Unmute' }).click()
+  const b = await vs()
+  let c = b
+  if (await page.getByLabel('Volume').count()) { await page.getByLabel('Volume').fill('0.3'); c = await vs() }
+  const kept = await page.evaluate(() => Object.entries(localStorage).find(([k]) => /volume/.test(k))?.[1] ?? '')
+  check('volume: mute, unmute, level, remembered', a.muted && !b.muted && (c.volume === 0.3 || !(await page.getByLabel('Volume').count())) && /level/.test(kept),
+    `${JSON.stringify(a)} → ${JSON.stringify(b)} → ${JSON.stringify(c)}, kept ${kept}`)
+  if (await page.getByLabel('Volume').count()) await page.getByLabel('Volume').fill('1')
+}
+
 // The 5-second buttons: back and on, the ball with them.
 {
   await controls()
diff --git a/web/src/Player.tsx b/web/src/Player.tsx
index 150b0d3..68dc5e6 100644
--- a/web/src/Player.tsx
+++ b/web/src/Player.tsx
@@ -53,6 +53,9 @@ class PatientAbr extends Base {
   }
 }
 
+// Whether the browser lets a page set the volume level (iOS doesn't: only mute).
+const canLevel = (() => { try { const a = document.createElement('audio'); a.volume = 0.5; return a.volume === 0.5 } catch { return false } })()
+
 const mbps = (b: number) => `${b >= 10e6 ? Math.round(b / 1e6) : (b / 1e6).toFixed(1)} Mb/s`
 const clock = (sec: number) => { const t = Math.max(0, Math.floor(sec)), h = Math.floor(t / 3600), m = Math.floor((t % 3600) / 60), x = t % 60; return `${h ? `${h}:${String(m).padStart(2, '0')}` : m}:${String(x).padStart(2, '0')}` }
 const size = (w?: number, h?: number, vr?: boolean) => {
@@ -68,6 +71,14 @@ const I = ({ d, size: sz = 20, fill }: { d: string; size?: number; fill?: boolea
 const PLAY = 'M7 4.5v15l12.5-7.5z', PAUSE = 'M8 5v14M16 5v14', CHECK = 'M5 12.5l4.5 4.5L19 7.5', TUNE = 'M4 7h10M18 7h2M4 17h4M12 17h8M16 5v4M10 15v4'
 const FULL = 'M4 9V4h5M20 9V4h-5M4 15v5h5M20 15v5h-5', SMALL = 'M9 4v5H4M15 4v5h5M9 20v-5H4M15 20v-5h5', PHONE = 'M8 3h8a1 1 0 0 1 1 1v16a1 1 0 0 1-1 1H8a1 1 0 0 1-1-1V4a1 1 0 0 1 1-1zM3 9a9 9 0 0 0 0 6M21 9a9 9 0 0 1 0 6'
 
+// The speaker: waves by the level, a cross when muted.
+const Speaker = ({ off, low }: { off?: boolean; low?: boolean }) => (
+  <svg width={20} height={20} viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="1.8" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true">
+    <path d="M4 9.5h3.5L12 5.5v13l-4.5-4H4z" fill="currentColor" />
+    {off ? <path d="M16 9.5l5 5M21 9.5l-5 5" /> : <path d={low ? 'M15.5 9.5a3.5 3.5 0 0 1 0 5' : 'M15.5 9.5a3.5 3.5 0 0 1 0 5M18 7a7 7 0 0 1 0 10'} />}
+  </svg>
+)
+
 // Five seconds back or on: a circling arrow with the 5 inside.
 const Skip = ({ back }: { back?: boolean }) => (
   <svg width={20} height={20} viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="1.8" strokeLinecap="round" strokeLinejoin="round" aria-hidden="true">
@@ -239,6 +250,17 @@ export default function Player({ path, sudo }: { path: string; sudo: boolean; na
     el.addEventListener('change', commit)
     return () => el.removeEventListener('change', commit)
   })
+  // Volume: a level and mute, remembered for the next video. iOS lets a page mute but not set
+  // the level (it reads back as 1), so there the slider isn't shown.
+  const [vol, setVol] = useState(() => { try { const v = JSON.parse(localStorage.getItem('hamlab.play.volume') ?? ''); return { level: Math.min(1, Math.max(0, Number(v.level) || 0)), muted: !!v.muted } } catch { return { level: 1, muted: false } } })
+  useEffect(() => {
+    const v = video.current
+    if (v) { v.volume = vol.level; v.muted = vol.muted || vol.level === 0 }
+    try { localStorage.setItem('hamlab.play.volume', JSON.stringify(vol)) } catch { /* private mode */ }
+  }, [vol, open])
+  const volBy = useCallback((d: number) => setVol((x) => ({ level: Math.round(Math.min(1, Math.max(0, x.level + d)) * 20) / 20, muted: false })), [])
+  const muteToggle = useCallback(() => setVol((x) => (x.muted || x.level === 0 ? { level: x.level || 0.5, muted: false } : { ...x, muted: true })), [])
+
   const seekBy = useCallback((d: number) => {
     const v = video.current
     if (!v) return
@@ -268,6 +290,9 @@ export default function Player({ path, sudo }: { path: string; sudo: boolean; na
     else if (e.key === 'ArrowLeft' || e.key === 'j') { e.preventDefault(); seekBy(e.key === 'j' ? -10 : -5) }
     else if (e.key === 'ArrowRight' || e.key === 'l') { e.preventDefault(); seekBy(e.key === 'l' ? 10 : 5) }
     else if (e.key === 'f') fullscreen()
+    else if (e.key === 'm') muteToggle()
+    else if (e.key === 'ArrowUp') { e.preventDefault(); volBy(0.1) }
+    else if (e.key === 'ArrowDown') { e.preventDefault(); volBy(-0.1) }
     else if (e.key === 'Escape') { if (menu) setMenu(false); else if (full && !document.fullscreenElement) setFull(false) }
   }
 
@@ -349,6 +374,12 @@ export default function Player({ path, sudo }: { path: string; sudo: boolean; na
           <button className="vp-icon" onClick={toggle} aria-label={paused ? 'Play' : 'Pause'}>{paused ? <I d={PLAY} fill /> : <I d={PAUSE} />}</button>
           <button className="vp-icon" onClick={() => seekBy(-5)} aria-label="Back 5 seconds" title="Back 5 seconds"><Skip back /></button>
           <button className="vp-icon" onClick={() => seekBy(5)} aria-label="On 5 seconds" title="On 5 seconds"><Skip /></button>
+          <span className="vp-vol">
+            <button className="vp-icon" onClick={muteToggle} aria-label={vol.muted || vol.level === 0 ? 'Unmute' : 'Mute'} title={vol.muted || vol.level === 0 ? 'Unmute (m)' : 'Mute (m)'}><Speaker off={vol.muted || vol.level === 0} low={vol.level < 0.5} /></button>
+            {canLevel && <input type="range" min={0} max={1} step={0.05} value={vol.muted ? 0 : vol.level} aria-label="Volume"
+              style={{ ['--v' as string]: `${(vol.muted ? 0 : vol.level) * 100}%` }}
+              onChange={(e) => { const level = Number(e.target.value); setVol({ level, muted: level === 0 }); poke() }} />}
+          </span>
           <span className="vp-time inrow">{clock(shown)} / {clock(dur)}</span>
           <span className="spacer" />
           {vr && canMotion() && (
diff --git a/web/src/styles.css b/web/src/styles.css
index b08e8e6..680e586 100644
--- a/web/src/styles.css
+++ b/web/src/styles.css
@@ -988,3 +988,12 @@ html:has(.vp)::before, html:has(.vp)::after, body:has(.vp)::before, body:has(.vp
 .vp video, .vp canvas { filter: none !important; mix-blend-mode: normal !important; }
 .vp { font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif; font-weight: 400; letter-spacing: normal; text-shadow: none; }
 .vp button, .vp input, .vp select { font-family: inherit !important; }
+
+/* volume: the speaker mutes; the slider beside it (not on iOS, which only mutes) sets the level */
+.vp-vol { display: inline-flex; align-items: center; }
+.vp-vol input { width: 72px; height: 24px; margin: 0 6px 0 0; padding: 0; background: transparent; border: 0; -webkit-appearance: none; appearance: none; cursor: pointer; }
+.vp-vol input::-webkit-slider-runnable-track { height: 4px; border-radius: 2px; background: linear-gradient(to right, #fff var(--v), rgba(255, 255, 255, .3) var(--v)); }
+.vp-vol input::-moz-range-track { height: 4px; border-radius: 2px; background: linear-gradient(to right, #fff var(--v), rgba(255, 255, 255, .3) var(--v)); }
+.vp-vol input::-webkit-slider-thumb { -webkit-appearance: none; width: 12px; height: 12px; margin-top: -4px; border-radius: 50%; background: #fff; border: 0; }
+.vp-vol input::-moz-range-thumb { width: 12px; height: 12px; border-radius: 50%; background: #fff; border: 0; }
+@media (max-width: 560px) { .vp-vol input { display: none; } }