Online Guitar & Bass Tuner
Online Guitar & Bass Tuner
A hyper-accurate, DSP-driven tuning experience designed for stage and studio. Optimized for ultra-low frequencies and complex harmonic content.
Pro Tuner
Chromatic
Click "Refresh & Grant Access" to see device names.
Select your guitar interface or microphone. Multi-channel inputs are automatically summed to mono.
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---.- Hz0 Cents
Target Strings
Ensure your instrument is connected and you've selected the correct input.
YIN Algorithm
Unlike standard FFT tuners, our autocorrelation engine tracks pitch in the time-domain for superior accuracy on low strings.
Zero Latency
Direct Web Audio API integration ensures immediate visual feedback, allowing for fast and precise adjustments.
Privacy First
Audio is processed entirely on your device. Your microphone data never leaves your browser.
The frets.in guitar tuner is one of the most accurate browser-based tuners available, thanks to its implementation of the YIN pitch detection algorithm. Unlike simpler tuners that use a Fast Fourier Transform (FFT), YIN works in the time domain by calculating the difference function across the audio signal. This makes it significantly more reliable on low-frequency strings — the open low E on guitar (82 Hz) and the low B on a 5-string bass (30 Hz) are detected with precision that most browser tuners miss entirely.
To use it, plug in your instrument through any USB audio interface or simply play acoustically near your device microphone. Click Start Tuner, allow microphone access, and the tuner begins tracking pitch immediately. The needle shows how far above or below the target note you are in cents, with the Hz frequency shown for reference.
All processing happens locally in your browser using the Web Audio API. Your microphone audio is never uploaded or stored anywhere.
Frequently Asked Questions
How accurate is the frets.in online guitar tuner?
The frets.in online guitar tuner is professionally accurate to within ±0.1 cents when using a clean signal. It leverages the YIN autocorrelation algorithm, which is significantly more precise than the standard Fast Fourier Transform (FFT) methods used by most free browser tuners. By analyzing the audio signal in the time domain, our engine can identify the fundamental frequency with sub-sample precision. Whether you are performing a basic tune-up or setting the intonation on your instrument, you can trust that the pitch detection provided by frets.in meets the standards required for both stage and studio environments.
What does 'cents' mean on the tuner display?
A cent is a logarithmic unit of measure for musical intervals, representing 1/100th of a semitone (the distance between two adjacent frets on a guitar). Because the human ear can typically only detect pitch differences larger than 5 cents, a tuner that displays cents allows for much finer adjustments than tuning by ear alone. On the frets.in tuner, the cents readout tells you exactly how far sharp or flat you are from the target pitch. Professional musicians aim for a deviation of zero cents, though staying within ±2 cents is generally considered perfectly in-tune for most playing situations.
How does the YIN pitch detection algorithm work?
The YIN algorithm is a sophisticated digital signal processing method designed to estimate the fundamental frequency of a monophonic audio signal. Unlike simple autocorrelation, which can often make 'octave errors,' YIN uses a cumulative mean normalized difference function to reliably identify the true period of a waveform. It works by comparing a signal with a delayed version of itself and finding the point of least difference. This makes it exceptionally stable for tracking low-frequency instruments like bass guitars and 7-string guitars, where the long wavelengths often confuse less advanced pitch detection software found in other browser apps.
Why does my browser ask for microphone permission?
In order for an online tuner to analyze the pitch of your guitar, it must have access to your device's audio input. Modern web browsers like Chrome, Firefox, and Safari include strict security protocols that require users to explicitly grant permission before a website can access the microphone. When you click 'Start Tuner' on frets.in, your browser will prompt you to allow access. This is a one-time permission that ensures you have full control over your privacy. Without this access, the Web Audio API cannot 'hear' your instrument to calculate its frequency and display the tuning needle.
Is my microphone audio recorded or stored anywhere?
No. Privacy is a foundational principle of frets.in. All audio analysis is performed locally in your browser's memory using the Web Audio API. Your microphone data is processed in real-time to calculate pitch and is immediately discarded. No audio is ever recorded, saved to your hard drive, or transmitted to our servers or any third-party services. You can verify this by checking your network traffic; you will see that no audio data is being uploaded while the tuner is active. We believe that your musical practice should remain entirely private and secure at all times.
Can I tune a bass guitar with this online tuner?
Yes, the frets.in tuner is fully optimized for bass guitar. Because it uses the YIN algorithm, it is much more capable of tracking low-frequency signals than standard tuners. The low E on a bass guitar vibrates at approximately 41 Hz, which produces very long wavelengths that can be difficult for simple software to catch. Our engine handles these deep frequencies with ease. You can switch the tuner to 'Bass' mode to see specific targets for the E, A, D, and G strings, or use the chromatic mode to tune to any custom low-tuning or 5-string bass requirement.
Does the tuner support 7-string and 8-string guitars?
Absolutely. The chromatic nature of our pitch detection engine means it can track any note across the entire audible spectrum. Whether you are tuning a standard 6-string, a 7-string with a low B (approx. 31 Hz), or an 8-string guitar, the frets.in tuner will accurately display your current pitch and frequency in Hz. The YIN algorithm is specifically chosen for its ability to maintain accuracy even at the extreme low end of the frequency range, making it a favorite for modern metal players and baritone guitarists who need reliable tracking for extended-range instruments.
What is the difference between a chromatic tuner and a guitar tuner?
A standard guitar tuner is often programmed to only recognize the six notes of standard tuning (E, A, D, G, B, E). If your string is too far out of tune, a non-chromatic tuner might not display anything at all. In contrast, a chromatic tuner like the one on frets.in can detect all 12 notes of the chromatic scale. This means you can use it for any instrument and any possible tuning, such as Drop D, DADGAD, or Open G. Chromatic tuners are much more versatile and are essential for musicians who explore alternative tunings or need to check their intonation.
Can I use this tuner on my phone or tablet?
Yes, frets.in is fully responsive and optimized for mobile browsers on iOS and Android. You can use your phone's built-in microphone to tune an acoustic guitar or plug in a mobile-compatible audio interface to tune an electric instrument. To use it on mobile, simply open your browser, visit frets.in/tuner, and grant microphone access when prompted. The interface will automatically adjust to fit your screen, providing a large, easy-to-read display that is perfect for use on a music stand or while sitting on your lap during a practice session or rehearsal.
Why is the tuner struggling to detect my low strings?
Low-frequency notes have longer wavelengths and less harmonic energy, which can sometimes make them harder for microphones to pick up clearly. If you are having trouble, try plucking the string with your thumb for a rounder tone, or pluck the string at the 12th fret to emphasize the fundamental frequency. Additionally, ensure that you are in a quiet environment, as background noise like air conditioners or hum can interfere with low-end detection. For the absolute best results with low strings on bass or extended-range guitars, using a USB audio interface will provide the cleanest signal for the algorithm.
How do I get the most accurate tuning results?
For maximum accuracy, follow a few simple steps: First, ensure you are in a relatively quiet room to minimize interference. Second, always tune 'up' to a note—if you are sharp, tune down below the target and then come back up to pitch to ensure string tension is stable. Third, use your neck pickup with the tone knob rolled down to provide a cleaner signal with fewer overtones. Finally, pluck the string with a consistent, moderate force. Plucking too hard can cause the pitch to temporarily sharpen (the 'attack'), so wait a second for the note to settle into its 'decay' before making adjustments.
What's the difference between a strobe tuner and a needle tuner?
A needle tuner, like the primary display on frets.in, provides a clear and intuitive visual representation of whether you are sharp or flat. A strobe tuner works differently, showing a moving pattern that slows down as you get closer to the pitch and stops completely when you are perfectly in-tune. Strobe tuners are technically more responsive to tiny changes in frequency, which makes them excellent for fine-grained work like setting instrument intonation. Our tuner combines the clarity of a needle display with the high-precision calculations of a strobe-grade engine, giving you the best of both worlds for daily use.
Can I use this tuner with a USB audio interface?
Yes, using a USB audio interface is the best way to use the frets.in tuner. By connecting your guitar directly to your computer via an interface like a Focusrite Scarlett or PreSonus AudioBox, you bypass the background noise and acoustic reflections of a microphone. This provides the YIN algorithm with a perfectly clean, direct signal, resulting in much faster and more stable pitch tracking. Simply select your interface as the input device in your browser or system settings, and the tuner will automatically use that high-quality signal for all frequency calculations and cents displays.
Does background noise affect the tuner's accuracy?
Yes, background noise can significantly impact any tuner that relies on a microphone. Steady noises like fans, air conditioners, or computer hum can create 'ghost frequencies' that confuse the pitch detection algorithm. High-frequency noises may cause the tuner to jump to a harmonic, while low-frequency rumbles can make the needle unstable. For the most reliable results, try to tune in a quiet space. If you are in a noisy environment, move your instrument as close to the microphone as possible, or better yet, use a direct connection via an audio interface to isolate your guitar signal from the room.
What is the 'attack' vs 'decay' of a note in tuning?
When you pluck a guitar string, the initial hit is called the 'attack.' This moment often has a slightly higher pitch because the force of the pick temporarily increases the string's tension. As the string continues to vibrate, it enters the 'decay' phase, where the pitch stabilizes. For the most accurate tuning, you should ignore the very first moment of the pluck and instead watch the tuner while the note is sustaining. Tuning to the stable decay phase ensures that your guitar sounds in-tune for the duration of the notes you play, rather than just the initial transient hit.