TuneReveal.com
Read a signature without hiding the spelling
This key signature finder is a local reference for conventional major and natural-minor keys. Choose a tonic and mode, and the result shows how many sharps or flats appear in the written signature, which pitch letters receive them, how the seven-note scale is spelled, and which relative and parallel keys are associated with the label.
It is a lookup, not a listening engine. The page does not inspect a score, chord progression, recording, URL, or microphone. A displayed signature answers “How is this entered key conventionally notated?” It does not answer “What key is my song in?”
Why the letters matter
A diatonic major or natural-minor scale uses each letter name once before returning to the tonic. That is why F-sharp major is written F-sharp, G-sharp, A-sharp, B, C-sharp, D-sharp, E-sharp rather than replacing E-sharp with the keyboard-equivalent F. The spelling communicates scale degree and harmonic function, not only piano-key position.
Key signatures also follow established accidental order. Sharps appear in the order F, C, G, D, A, E, B. Flats appear in the reverse-related order B, E, A, D, G, C, F. The tool displays the applicable prefix of that order for the supported key.
Natural minor uses the same signature as its relative major. That does not mean the two keys have the same tonic or behave identically. It means their basic diatonic collections share pitch classes before harmonic or melodic minor alterations are considered.
How to use the lookup
Select a tonic such as E-flat, choose Major, and leave the enharmonic display preference on Conventional. Press “Find key signature.” The result separates four ideas:
- Signature: the accidentals written at the beginning of a staff.
- Scale spelling: the seven notes in tonic order.
- Relative key: the major or minor key sharing that signature.
- Parallel key: the opposite mode beginning on the same tonic.
If you prefer a valid enharmonic display, the tool may offer an alternate common label. It will not casually respell a key when doing so would create double sharps or double flats outside the launch table. A scope message is more useful than a superficially neat but pedagogically misleading answer.
Worked example: E-flat major
Choose E-flat and Major. The result is three flats: B-flat, E-flat, and A-flat. The scale spelling is E-flat, F, G, A-flat, B-flat, C, D. C minor appears as the relative minor because it uses the same three-flat signature. E-flat minor appears as the parallel minor because it keeps the E-flat tonic while changing mode; its signature is different.
Suppose a chorus emphasizes C minor even though the signature shown in a score has three flats. The lookup cannot decide whether E-flat major or C minor is the governing key. That question requires tonal evidence: arrival points, bass support, cadences, melodic emphasis, and larger form. The relative-key guide explains why shared materials permit two different centers.
Worked spelling contrast: F-sharp and G-flat
F-sharp major and G-flat major sound enharmonic in twelve-tone equal temperament, but their written scales and signatures differ. F-sharp major uses six sharps; G-flat major uses six flats. A performer or arranger may choose one spelling because it fits surrounding harmony, instrument conventions, readability, or modulation.
The display preference helps compare common alternatives without asserting that notation is interchangeable in every context. Correct spelling is relational. A note that sounds the same on a fixed-key instrument can carry a different structural role.
What the tool covers
The launch table focuses on commonly notated major keys and natural-minor counterparts through signatures of up to seven sharps or flats. It reports the key signature, not every accidental that may occur in music. Harmonic minor commonly raises scale degree seven in context, and melodic minor conventions alter degrees six and seven in ways not encoded as a permanent key signature.
The result does not cover modes as independent signature decisions, non-Western pitch systems, microtonal notation, transposing-instrument parts, historical signatures, open-key notation, figured bass, or a composer’s intentional enharmonic reinterpretation. It assumes contemporary staff-notation conventions.
Use the result as a check
When writing or reading a passage, compare the result with the actual accidentals and harmonic behavior. If a score has frequent chromatic changes, a signature may be a practical notation choice rather than a complete analytical statement. If you are transposing, open the transposer only after deciding how the destination key should be spelled.
For a listening task, first note the suspected tonic and the passage that supports it. Then use this page to check what the conventional signature would contain. That sequence prevents the lookup table from becoming circular evidence for the key you already selected.
Frequently asked questions
Does a key signature prove the key?
No. Relative major and minor keys share signatures, and modal or chromatic music can use the same notated collection in other ways.
Why is E-sharp shown instead of F in F-sharp major?
Each diatonic scale degree needs a distinct letter. E-sharp is the seventh degree leading to F-sharp; writing F would duplicate the tonic letter.
Does natural minor include a raised seventh?
Not in the basic signature. A raised seventh used for harmonic function appears as a contextual accidental.
Can the page read a photo of sheet music?
No. There is no image upload or optical recognition. You select the key label yourself.
Choose the tonic and mode, then select “Find key signature.” Read the accidental order and scale spelling before copying the result. If the musical center is still uncertain, return to the listening guide rather than treating notation as a verdict.