Guitarists
Tune acoustic or electric in standard, then use the Drop D guitar tuner preset or Drop C for a song. Learning it from a recording? Turn it into tabs with the guitar tab generator, or into notes with the audio to MIDI converter.
Free Online Tuner for Guitar, Bass, Ukulele and Violin
ToMIDI is a free online tuner that listens through your microphone: play one string and the needle shows which way to turn the peg, then lights up green when the string is in tune. Pick guitar in standard, Drop D, Drop C, DADGAD or an open tuning, or bass, ukulele, violin, viola or cello, or switch to the chromatic tuner for any note. It runs in your browser, nothing is recorded or uploaded, and every string has a reference tone for tuning by ear.
- Drop D and Drop C Presets
- Auto String Detection
- Reference Tones
- Nothing Uploaded
Tune your guitar with your microphone
Your strings are detected automatically. Audio stays on your device.
- Runs in your browser, nothing is uploaded
- Reference tones for every string
- Free, no sign-in
Tune one string at a time and let it ring. Strummed chords and loud rooms can't be read; very low bass strings settle more slowly on phone and laptop mics.
Tap a peg to hear its note
No microphone? Tap a peg to hear each string and tune by ear.
- Spacestart / stop
- 1…6pick a string
- AAuto detect
- Preplay tone
- SStrobe
How This Online Tuner Works
An online tuner hears one note through your microphone, measures its frequency and compares it with the string you are tuning. The needle shows how many cents flat or sharp you are: left of centre means tune up, right means tune down, and the string turns green within 3 cents. Pick your instrument and tuning, pluck a string, and the guitar tuner works out which string you played on its own. Everything happens in your browser, so the sound is analysed on your device and never recorded. Want the exact note of anything you sing or play, with a pitch graph? Use the pitch detector.
Start TuningWhy Use This Free Guitar Tuner
Six reasons to use this guitar tuner instead of hunting for a clip-on or installing an app.
Eight modes, 22 presets
Guitar in 11 tunings, bass with 4 or 5 strings, ukulele in high G, low G, baritone and D tuning, plus violin, viola, cello, a chromatic tuner and a voice mode.
Finds the string for you
Auto mode picks the string closest to what it hears. Tap a string to pin the needle to it when a string is so far out that it sounds like its neighbour.
Needle or strobe view
Read a classic needle or switch the online tuner to its strobe view for fine tuning. A strip underneath draws the last six seconds, so drift and slow settling are easy to spot.
Reference tones
Every string has a reference tone, as a plucked string or a pure sine, so you can tune by ear or check your ear against the needle.
A4 from 415 to 466 Hz
Stay at 440, choose 442 for many orchestras, 432 if your band uses it, or 415 for baroque pitch. Every target and every tone follows.
Free and private
No account and no app to install. The microphone is analysed in this tab, and your instrument and settings are remembered in your browser.
How to Tune a Guitar With the Online Tuner
Six strings take about a minute with the online tuner. Here is the whole routine.
Press Start and allow microphone access. Hold your phone or laptop 15 to 30 cm from the sound hole or the amp. No microphone? Tap a string to hear its reference tone instead.
Choose Guitar, Bass, Ukulele, Violin, Viola, Cello, Chromatic or Voice, then a tuning such as Standard, Drop D or Drop C. The guitar tuner's string buttons change to the notes you need.
Pluck a single open string and let it ring. Needle left of centre: the string is flat, so tighten it. Right of centre: sharp, so loosen it. Small turns work best.
The note turns green within 3 cents and the string gets a check mark after about half a second in tune. Go across all strings a second time, because each change pulls on the neck a little.
Step 1 · Press Start and allow the microphone
Inside the Online Guitar Tuner
Five tools that cover every instrument and tuning, from standard EADGBE to a five-string bass.
Auto string detection, or pin a string
In auto mode the tuner matches each note to the nearest string of your tuning and allows for the octave slips that low strings can cause. When a string is far out, after a string change or a big tuning change, it may sound closer to its neighbour. Tap the string you are tuning to pin it: the needle then measures only against that note and counts the semitones left to go, so you can bring a slack string up without guessing. On a keyboard, Space starts and stops, the number keys pick a string, A returns to auto, S swaps needle and strobe and P replays the reference tone.
Try Auto DetectionA Drop D tuner, Drop C and nine more guitar tunings
Pick a tuning and the guitar tuner switches its targets: Standard, Drop D, Half step down, D Standard, Drop C, Drop B, DADGAD, Open G, Open D, Open E and Open C. Each string button shows its new note with the octave, such as D2 for a dropped 6th string. Acoustic or electric guitar tuner, Drop D is one menu pick away, and the Drop B guitar tuner preset goes lowest. Use it as a Drop C tuner. Guitar strings get looser as you go down, so pin each string before you lower it.
Pick a TuningBass tuner, ukulele tuner, violin tuner and cello
The bass tuner covers 4-string standard (E1 A1 D2 G2), 5-string with a low B0, Drop D and half step down. The ukulele tuner has standard GCEA with a high G, low G, baritone (DGBE) and D tuning (ADF♯B). The violin tuner reads G3 D4 A4 E5, and the viola tuner and cello tuner both work in fifths on C, G, D and A. Bowed notes ring long and give a steady reading. A low B is faint on phone and laptop microphones, so tune its 12th-fret harmonic in chromatic mode if the needle wanders.
Choose Your InstrumentA chromatic tuner for any instrument, and a voice mode
Chromatic mode drops the string presets and names whatever note it hears, with its octave, frequency and cents. Use the chromatic tuner for mandolin, banjo, flute, horns or a single piano string, and for tunings that are not in the list, such as a Drop E tuner setup or a Drop C bass tuner (C G C F). Voice mode does the same for singing. The strobe view helps with the last few cents: its bands drift while you are off and settle when you are in tune.
Open Chromatic ModeReference tones, A4 calibration and a no-mic demo
Tap the speaker on any string to hear its target as a plucked string or a clean sine, then match it by ear: handy in a loud room or on a device with no working microphone. A4 starts at 440 Hz and goes from 415 to 466, and every target and tone follows it. Want to see how it behaves before you allow the microphone? The demo plays a detuned string and shows the needle bring it into tune. Then keep time with the metronome.
Hear the Reference TonesGuitar Tuner Chart: Every Preset With Notes and Hz
All 22 presets from the tuner, with the exact target of every string. Pick an instrument and a tuning, change A4, and tap a string to hear it.
A4440 Hz
Guitar · Standard
E A D G B E
thickest string first differs from standardequal temperament from A4 = 440 Hz
What you are looking at
These are the targets the online tuner aims for, worked out from A4 with equal temperament. At 440 Hz, standard guitar tuning reads E2 82.41, A2 110.00, D3 146.83, G3 196.00, B3 246.94 and E4 329.63 Hz, from the thickest string to the thinnest, and the Drop D guitar tuner preset changes only the first of them, to D2 at 73.42 Hz. Ukulele standard tuning is re-entrant: its G4 string sits above C4. The tones here are a quick reference; the tuner above has the full pluck and sine tones.
Drop D Tuner and Drop C Tuner: String by String
The two most searched alternate tunings and two close relatives. Start from standard tuning and change only what is listed.
Drop D (D A D G B E)
Select the Drop D tuning: guitar tuner targets become D2 A2 D3 G3 B3 E4. Lower only the 6th string a whole step, to 73.42 Hz. Check it by ear: the 6th string at the 7th fret matches the open A.
Drop C (C G C F A D)
Lower every string a whole step to D Standard, then the 6th string one more step to C2 at 65.41 Hz. The Drop C guitar tuner CGCFAD preset shows every target; the 7th fret of the 6th string matches the open G.
Half step down (E♭ A♭ D♭ G♭ B♭ E♭)
Every string down one semitone, the low string at 77.78 Hz. Common in rock and blues to match recordings and ease a singer's key without new chord shapes.
Drop B and Open D
Drop B (B F♯ B E G♯ C♯) goes lower for modern metal; a heavier string set stops the buzz. Open D (D A D F♯ A D) rings a D major chord for slide and folk. Both are presets in the online tuner, Open D included.
When the Online Tuner Needle Jumps
A guitar tuner needs one clear note that is louder than the room. With a single string ringing in a quiet room, the needle settles quickly. Your microphone and your space matter more than the maths, so if the reading wanders, check these first.
- Two strings ringing or a strummed chord: the online tuner follows one note. Mute the strings you are not tuning with your fretting hand.
- A loud room: turn on Noisy room, which ignores quieter sounds and unclear notes, and move the microphone closer.
- The first instant of a pluck is noisy. Let the string ring for a moment before you read the needle.
- Low bass strings, the B0 above all, are faint on phone and laptop microphones. Tune the 12th-fret harmonic in chromatic mode.
- Distortion, chorus and delay blur the pitch. Switch effects off on an electric guitar while you tune.
- A string far from its target can read as the next string. Tap the string to pin it.
Online Tuner vs Clip‑on Tuner vs Tuner Apps
A clip-on tuner feels vibration through the headstock, a pedal reads the guitar cable, and phone apps and this online tuner listen through a microphone. Each has a place. We compare how they work, not quality.
| This siteToMIDI | Clip-on tuner | Pedal tuner | Phone tuner apps | |
|---|---|---|---|---|
| Cost | Free, nothing to install | Buy one | Buy one, plus a cable | Free or paid, install needed |
| How it hears | Microphone | Vibration through the headstock | Direct from the instrument cable | Microphone |
| Loud stage | Not ideal; use a clip-on on stage | Yes | Yes | Usually not |
| Tunings and instruments | 22 presets plus chromatic and voice | Often chromatic only | Often chromatic only | Varies |
| Reference tones | Yes, pluck or sine | No | No | Varies |
| Strobe view | Yes | Some models | Some models | Varies |
| Your audio | Stays on your device | No audio captured | No audio captured | Varies |
Who Uses This Guitar Tuner Online
From a first ukulele lesson to a dropped-tuning metal riff: anyone with strings, a microphone and this online tuner.
Bass players
The bass tuner covers four and five strings, Drop D and half step down. For lines you want on paper, the bass tab generator writes them out.
Ukulele players and beginners
The ukulele tuner's clear string buttons and reference tones help new players learn what in tune sounds like, in high G or low G.
Orchestra and string players
Violin, viola and cello presets, with A4 at 442 for orchestras that tune bright, and long bowed notes that the needle reads steadily.
Singers and choirs
Voice mode shows the note you hold. For a scrolling pitch graph, target notes and a range test, open the pitch detector.
Teachers and classes
Put the tuner on a big screen so the room sees each string come into tune, then name the chords of the lesson with the chord finder.
Online Tuner FAQ
Real questions about tuning online, answered plainly, limits included.
How do I tune my guitar with an online tuner?
Press Start, allow the microphone and choose Guitar with Standard tuning. Pluck the low E string and let it ring, then turn the peg until the needle sits in the middle and the note turns green. Repeat for A, D, G, B and high E, then check all six once more.
What are the notes and frequencies of standard guitar tuning?
From the thickest string to the thinnest: E2 82.41 Hz, A2 110.00 Hz, D3 146.83 Hz, G3 196.00 Hz, B3 246.94 Hz and E4 329.63 Hz, with A4 at 440 Hz. Many players remember the order as "Eddie Ate Dynamite, Good Bye Eddie".
How do I tune to Drop D with this tuner?
Open the guitar tuner: Drop D is in the Tuning menu. Strings 1 to 5 stay as they are. Tap the 6th string to pin it, then lower it a whole step from E2 to D2 until the needle centres. With any Drop D tuner, guitar players also check by ear: the 6th string at the 7th fret should match the open A.
Is there a Drop C tuning guitar tuner preset?
Yes. Pick Drop C (C G C F A D), lower every string a whole step, then take the 6th string one more step to C2 at 65.41 Hz, pinning each string first so the needle aims at its new note. Open the guitar tuner, Drop C sits next to Drop D in the menu. If you came for Drop C tuning, online tuner presets for Drop B and D Standard are right beside it too.
Why does the tuner show the wrong string?
Auto mode guesses the string from the note it hears, so a string tuned far from its target can sound like its neighbour. Tap the string you are tuning to pin it; the needle then measures only against that note and shows how many semitones away you are. Switch back to auto when you are done.
How accurate is this online tuner?
The note turns green within 3 cents of the target and stays green until it drifts past 6, and a string earns its check mark after about half a second in tune. So far we have measured synthetic tones in Edge only: a low E, an A 12 cents flat, a D 8 cents sharp, a Drop C string 2 cents sharp and the B0 of a 5-string bass all read correctly. Real strings depend on your microphone and your room, and we quote no figure for them until we have tested them.
Can I tune a bass, including a 5-string?
Yes. The bass tuner has 4-string standard (E1 A1 D2 G2), 5-string with a low B0 at 30.87 Hz, Drop D and half step down. Phone and laptop microphones hear little of the lowest notes, so the low B is fair at best: if the needle wanders, tune the 12th-fret harmonic in chromatic mode, an octave higher.
What is the difference between high G and low G ukulele tuning?
Standard ukulele tuning, G4 C4 E4 A4, is re-entrant: the 4th string is higher than the 3rd, which gives the bright, close sound. Low G drops that string an octave to G3 for a fuller bass. The ukulele tuner has both, plus baritone (D G B E) and D tuning (A D F♯ B).
Does it work as a violin tuner, viola tuner or cello tuner?
Yes. Violin is G3 D4 A4 E5, viola C3 G3 D4 A4 and cello C2 G2 D3 A3, all in fifths. Many string players tune the A first and the rest after it, and orchestras often set A4 to 442.
How do I use the chromatic tuner?
Choose Chromatic and play any note: the tuner names the nearest note with its octave, frequency and cents, with no string presets. Use it for mandolin, banjo, wind instruments, a single piano string or any tuning that is not in the list.
Should I tune to A4 = 440 Hz, 432 Hz or 442 Hz?
Stay at 440 Hz unless the people or the recording you play with use something else: it is the international standard and matches nearly all recorded music. Orchestras often use 442, about 8 cents higher, baroque groups 415, and a guitar at 432 sits about 32 cents low, so it clashes with instruments at 440.
Can I tune without a microphone or by ear?
Yes, by ear. Tap a string to hear its reference tone as a pluck or a sine and match your string to it; the needle needs the microphone, the tones do not. To tune strings to each other, use the 5th fret method: the 5th fret of each string matches the next open string, except on the G string, where the 4th fret matches the open B.
Does the online tuner work on iPhone and Android?
Yes, in Safari, Chrome, Edge and Firefox on phones, tablets and computers, over https. Allow the microphone when asked; if you said no before, turn it back on in the site settings from the address bar. On most phones the microphone sits on the bottom edge, so point that toward the sound hole.
Is my microphone audio recorded or uploaded?
No. The sound is analysed inside this browser tab while you tune and is never recorded, stored or sent to us. Stop releases the microphone. Your instrument, tuning and A4 setting stay in your browser, so the tuner opens the way you left it.
Why does my guitar keep going out of tune?
New strings stretch for a day or two, temperature and humidity move wood and metal, and a string that slips around its post creeps flat. Tune up to the note rather than down to it: if you overshoot, drop below and come back up so the string settles against the gear.
Can the tuner read a strummed chord?
No. It follows one note at a time, so play each string on its own. To name a chord you are playing, use the chord finder.
More Free Tools for Players
From Tuned Strings to Tabs and MIDI
- Guitar Tab GeneratorTurn guitar recordings into tabs.
- Guitar to MIDI ConverterTurn guitar riffs and leads into MIDI.
- Bass Tab GeneratorTurn bass lines into tabs.
- MIDI to Guitar TabConvert MIDI parts into playable tabs.
- Audio to MIDI ConverterTurn any recording into an editable MIDI file.
- Voice to MIDIHum, sing or whistle a melody into notes.
Tune Up Now With the Free Online Tuner
Press Start, pluck a string and turn until it glows green. Guitar, bass, ukulele, violin, viola or cello, standard or Drop D: the online tuner is free, runs in your browser and never uploads a sound.