Free browser tuner
Online Chromatic Tuner: All 12 Notes, Free Strobe
The DSP behind the chromatic tuner
StroboPro has grown from more than 15 years of original DSP development. The tuner uses FFT analysis to help identify the played note, then uses advanced, filtered, phase-based strobe processing for the fine movement you see on screen. Independent harmonic rings let the fundamental and upper partials show their own behavior instead of collapsing the whole sound into one number.
The result is a chromatic tuner that stays useful when you change instruments, registers, or tuning systems: the note recognition is broad, while the pitch feedback remains detailed.
What an online chromatic tuner is
Where a guitar-only tuner shows six preset buttons for E A D G B E and ignores anything outside standard, a chromatic tuner reads any note in any octave. Same page, any instrument.
StroboPro is fully chromatic, so one page covers guitar, bass, ukulele, violin, cello, mandolin, brass, woodwinds, and anything else that produces a detectable pitch. If you can hum it, pluck it, or blow into it, the tuner tells you what note it is and how far it sits from the nearest semitone.
That matters more than people expect. A horn player warming up in Bb, a singer checking a tricky interval, and a guitarist trying an alternate tuning all want the same tool: one that follows the instrument rather than the other way round.
Chromatic vs dedicated instrument tuners
A dedicated ukulele or violin tuner is convenient because it only shows the strings you care about. But the moment you use an alternate tuning, swap instruments, or work with a brass transposition, the dedicated tuner becomes the wrong tool.
A chromatic tuner trades that single-instrument convenience for universality. The same page tunes your guitar in standard, your friend's ukulele in D tuning, the trumpet player's Bb part, and the singer's vocal warm-up. For anyone who plays more than one instrument, a chromatic tuner is the more useful default.
Reference tones and tuning by ear
Some players prefer to tune by ear with a reference tone, especially in noisy rooms where a mic tuner struggles. StroboPro's mobile app includes a Pitch Pipe that plays reference tones for any note, so you can match by ear when the room is too loud for the mic.
Tuning against a reference tone also teaches you what an in-tune string actually sounds like, and that transfers to fretless instruments and vocal pitch.
Why a strobe chromatic tuner reads steadier
The strength of a chromatic strobe is that the same display stays readable whatever you point at it - a low piano note, a violin E, a sax multiphonic, a humming singer. A single-number needle has to re-average every time the instrument changes; the strobe just tracks whatever fundamental is present.
Each harmonic ring shows one overtone settling, and because StroboPro is chromatic across the whole range you never switch modes between instruments. That matters most for slow, low fundamentals (bass, piano, pipe organ), where a needle jumps by whole cents and the rings keep moving smoothly.
It also makes intonation work reliable across instruments: the gap between a 12th-fret harmonic and the fretted note is often under a cent, and the strobe shows that gap instead of rounding it away.
Free, browser-based, no install
The web tuner at strobopro.se is free, asks for no account, and processes audio locally in your browser. It installs as a Progressive Web App, so once you have visited you can keep tuning offline. See also our online tuner and online guitar tuner pages.
Also a native iOS and Android app
For offline chromatic tuning, the same engine ships as native iOS and Android apps. The mobile build carries the premium features: a Pitch Pipe that plays any reference note for ear tuning, an AI tuning generator, Echo Mode for vision-impaired players, a Piano Tuning Assistant, and Cloud Sync. The web tuner stays free.
For the full breakdown see the best guitar tuner app page, or the best bass tuner page for low-frequency use.
Read the blog
For background on what a strobe tuner is and why it has survived from the hardware bench into modern web apps, read the article on the StroboPro blog:
Read "What is a strobe tuner and how does it work?" on the blog →Related guides
Frequently asked questions
What is an online chromatic tuner?
A webpage that recognises all 12 notes through your browser mic, so it can tune any instrument in any key. StroboPro is fully chromatic - open [strobopro.se](https://strobopro.se/), tap the **Tap to Tune** button (the one with the microphone), and allow mic access. No install, no account.
Can a chromatic tuner tune instruments other than guitar?
Yes. Because it reads all 12 notes, the same tuner handles guitar, bass, ukulele, violin, mandolin, banjo, brass, woodwinds, and piano. Try it on the [free chromatic tuner](https://strobopro.se/).
Does StroboPro include reference tones for tuning by ear?
Yes. The Pitch Pipe in the mobile app plays reference tones for any note, useful in noisy rooms where a mic tuner struggles, or for ear training. The web tuner is strobe-only and uses your mic.
Published by Applicaudia, the maker of StroboPro. Resolution and frequency figures describe the tuner's design and display; they are not lab-measured accuracy specifications.
Open the free StroboPro tuner