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    YoutubeMusic Theory Video SeriesA step-by-step guide to music theory fundamentals. These 60-second videos provide a clear, structured path to understanding how music works, optimized for a full-screen learning experience.YoutubeMusic Theory ShortsMaster music theory concepts in 60 seconds or less. Quick, vertical videos designed to give you essential theory knowledge in a fast-paced, mobile-friendly format.
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    1. Home
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    4. How to Read Chord Symbols

    How to Read Chord Symbols

    Learn a simple way to read chord symbols. Start with the root, read the quality, add the seventh, then check added notes, extensions, and alterations.


    Author: Lida van der Eijk
    June 18, 2026

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    Chord symbols can look like a secret code. You may see C, then Cm7, then C13♭9. If you try to learn each symbol as a separate word, it gets hard fast.

    Use a better method: read the symbol as a set of steps. Find the root. Read the quality. Add the seventh if there is one. Then add extra notes or alterations. In this guide, we use C as the example root, so you can see each note clearly.

    CDEFGAB

    On this page
    • Chords start as stacked thirds
    • How the numbers work in chord symbols
    • Quality: major, minor, suspended, augmented, diminished
    • Major quality
    • Minor quality
    • Suspended quality
    • Augmented quality
    • Diminished quality
    • Sevenths, added notes, and extensions
    • Alterations: what can be lowered or raised?
    • A practical reading order
    • Outro
    Music theory libraries
    On this page
    • Chords start as stacked thirds
    • How the numbers work in chord symbols
    • Quality: major, minor, suspended, augmented, diminished
    • Major quality
    • Minor quality
    • Suspended quality
    • Augmented quality
    • Diminished quality
    • Sevenths, added notes, and extensions
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    Basics
  1. Alterations: what can be lowered or raised?
  2. A practical reading order
  3. Outro
  4. Music theory libraries
    Chord libraryScale libraryInterval guide

    Use this C major scale as your map: C is 1, D is 2, E is 3, F is 4, G is 5, A is 6, and B is 7. Chord symbols use these numbers all the time.

    Chords start as stacked thirds

    Most chords are built by stacking thirds. Start on C. Skip one note each time. You get C-E-G-B-D-F-A. As numbers, that is 1-3-5-7-9-11-13.

    Start small:

    • 1-3-5 gives a triad: C-E-G.
    • 1-3-5-7 gives a seventh chord.
    • 1-3-5-7-9 gives a ninth chord.

    When you read a chord symbol, ask: how much of this stack do I need, and which notes change?

    How the numbers work in chord symbols

    Every number is counted from the root. If you want more background first, read our guide to perfect intervals. Here is the practical map for C:

    NumberInterval from CNoteWhat to do when you see it
    1RootCUse C as the home note. Measure every other note from C.
    2SecondDIn Csus2, use D instead of the third. In Cadd2, add D without adding a seventh.
    3ThirdE or E♭Use it to decide the quality. C has E. Cm has E♭. You do not write C3 because the quality already tells you this.
    4FourthFIn Csus4, use F instead of the third. In bigger chords, this note is usually called 11.
    5FifthGAdd G as the normal fifth. Only think about it if the symbol changes it, like ♭5 or ♯5.
    6SixthAAdd A to the triad. C6 means C-E-G-A. It does not add a seventh.
    7SeventhB or B♭Add a seventh. Cmaj7 uses B. C7 and Cm7 use B♭.
    8OctaveCThis is C again. Chord symbols do not normally write 8.
    9Second above the octaveDAdd D as an upper color. C9 means C7 plus D. Cmaj9 means Cmaj7 plus D.
    10Third above the octaveEThis is the third again. Chord symbols do not normally write 10.
    11Fourth above the octaveFAdd F as an upper color. C11 means you are reading an extended chord.
    12Fifth above the octaveGThis is the fifth again. Chord symbols do not normally write 12.
    13Sixth above the octaveAAdd A as an upper color. C13 means a seventh chord with 13th color.

    Use this table as a checklist. Read the number, find the note, then ask what job that note has in the chord.

    Quality: major, minor, suspended, augmented, diminished

    Quality tells you what happens to the basic chord. It mostly changes the third and fifth. If major and minor still feel unclear, start with the difference between major and minor.

    Major quality

    A plain chord name is major. C means 1-3-5: C-E-G. You do not need to write “major” every time. The plain letter already tells you to use the major third.

    Synthesizer panel decorationOSCFLTENVLFOVOLOUTPUT
    Piano keyboardCEG

    Minor quality

    Minor lowers the third. Cm means 1-♭3-5: C-E♭-G. The m tells you to change E into E♭.

    Synthesizer panel decorationOSCFLTENVLFOVOLOUTPUT
    Piano keyboardCEG

    Suspended quality

    Suspended chords remove the third. Csus2 means 1-2-5: C-D-G. Csus4 means 1-4-5: C-F-G. Read the number after “sus” as the note that replaces the third.

    Augmented quality

    Augmented raises the fifth. Caug or C+ means 1-3-♯5: C-E-G♯. The plus sign is a quick way to show the raised fifth.

    Diminished quality

    Diminished lowers the third and the fifth. Cdim or C° means 1-♭3-♭5: C-E♭-G♭. If you see Cm7♭5, read it as a minor seventh chord with a lowered fifth.

    Sevenths, added notes, and extensions

    Read this part in two steps. First, check if the symbol adds a seventh. Then check if it adds another note, like 9 or 13.

    A plain 7 means a minor seventh. In C, that is B♭. If the chord needs B natural, the symbol must say maj7 or Δ7. For a focused next step, review the major seventh chord.

    SymbolThirdSeventhFormulaNotes in C
    C7Major thirdMinor seventh1-3-5-♭7C-E-G-B♭
    Cmaj7Major thirdMajor seventh1-3-5-7C-E-G-B
    Cm7Minor thirdMinor seventh1-♭3-5-♭7C-E♭-G-B♭
    Cm(maj7)Minor thirdMajor seventh1-♭3-5-7C-E♭-G-B

    Now add the next part of the symbol. Add means “add this note to the chord so far.” It does not add a seventh by itself. An extension like 9, 11, or 13 usually means there is a seventh under it.

    SymbolWhat to doFormulaNotes in C
    Cadd9Play C, then add D. Do not add a seventh.1-3-5-9C-E-G-D
    C9Play C7, then add D.1-3-5-♭7-9C-E-G-B♭-D
    Cmaj9Play Cmaj7, then add D.1-3-5-7-9C-E-G-B-D
    Cm9Play Cm7, then add D.1-♭3-5-♭7-9C-E♭-G-B♭-D
    C6Play C, then add A. Do not add a seventh.1-3-5-6C-E-G-A
    C13Play a dominant seventh chord with 13th color.1-3-5-♭7-9-11-13C-E-G-B♭-D-F-A
    Cmaj13Play a major seventh chord with 13th color.1-3-5-7-9-11-13C-E-G-B-D-F-A

    So Cadd9 and C9 are not the same. Cadd9 is a triad with D added. C9 is C7 with D added. The same idea applies to C6, Cadd13, C13, and Cmaj13: first check if the symbol adds a seventh, then add the color note.

    Alterations: what can be lowered or raised?

    An alteration moves a note by one half step. A flat lowers the note. A sharp raises it. If those signs are new to you, read the difference between sharp and flat. First read the basic chord. Then apply the alteration.

    DegreePossible alterationExample from CHow it is usually writtenPractical note
    1♭1 / ♯1C♭ / C♯Not written as an altered degreeIf the root changes, the chord name changes: C♯m7, not C♯1m7.
    2♭2 / ♯2D♭ / D♯Usually ♭9 or ♯9In extended chords, changed 2nds are written as changed 9ths.
    3♭3E♭Cm, Cm7, Cm9Do not write ♭3 in normal symbols. The minor quality already tells you this.
    3♯3E♯Almost never usedIt is usually clearer to spell the chord another way.
    4♯4F♯Usually ♯11In extended chords, a raised 4 is written as ♯11.
    4♭4F♭Almost never usedF♭ sounds like E, so it repeats the third.
    5♭5G♭Cdim, Cm7♭5, C7♭5Use it for diminished sounds or altered dominant chords.
    5♯5G♯Caug, C7♯5, Cmaj7♯5Use it for augmented sounds or altered dominant chords.
    6♭6A♭Usually ♭13If a seventh is present, write this sound as ♭13.
    6♯6A♯Almost never usedA♯ often sounds like B♭, the minor seventh.
    7♭7B♭C7, Cm7A plain 7 symbol already implies this note.
    7𝄫7B𝄫C°7Use it for fully diminished seventh chords.
    77 naturalBCmaj7, Cm(maj7)Write maj7 when you want the natural seventh.
    8♭8 / ♯8C♭ / C♯Not used in normal chord symbols8 repeats the root.
    9♭9D♭C7♭9Add a lowered ninth to the chord.
    9♯9D♯C7♯9Add a raised ninth to the chord.
    10♭10 / ♯10E♭ / E♯Not used in normal chord symbols10 repeats the third.
    11♯11F♯C7♯11, Cmaj7♯11Add a raised eleventh.
    11♭11F♭Almost never usedF♭ repeats the major third.
    12♭12 / ♯12G♭ / G♯Not used in normal chord symbols12 repeats the fifth. Write ♭5 or ♯5 instead.
    13♭13A♭C7♭13Add a lowered thirteenth.
    13♯13A♯Almost never usedA♯ often sounds like B♭, the minor seventh.

    Example: C7♭9 means C7 first: C-E-G-B♭. Then add D♭. The formula is 1-3-5-♭7-♭9.

    Another example: C7♯5♭9 means C7, raise the fifth, and lower the ninth. The notes are C-E-G♯-B♭-D♭.

    A practical reading order

    Use this order when a symbol looks hard:

    1. Find the root: C, F♯, B♭, and so on.
    2. Read the quality: major, minor, suspended, augmented, or diminished.
    3. Add the sixth or seventh: C6, C7, Cmaj7, Cm7.
    4. Add extra notes: add9, 9, 11, 13, add13.
    5. Apply alterations: ♭5, ♯5, ♭9, ♯9, ♯11, ♭13.

    Try it with Cm7♭5. Root: C. Quality: minor. Seventh: ♭7. Alteration: ♭5. Formula: 1-♭3-♭5-♭7.

    Synthesizer panel decorationOSCFLTENVLFOVOLOUTPUT
    Piano keyboardCGE♭B♭

    Try it with Cmaj9. Root: C. Quality: major. Seventh: maj7. Extra note: 9. Formula: 1-3-5-7-9.

    Outro

    Now put the method to work. Pick one chord symbol from a song or chart. Say the root, name the quality, add the seventh, then check for extra numbers or alterations. Write the formula before you play it.

    Try this with three symbols today: Cmaj7, Cm9, and C7♭9. If you can explain each one as intervals, you are reading the symbol instead of guessing it.

    Want to keep building this skill? Read the ultimate guide to understanding music, or open Sonid and explore chords, intervals, and scales side by side. Use it as a quiet practice tool: read the symbol, check the notes, listen to the sound, and repeat.

    Turn this into practice — try the major chord in a quick Sonid exercise.

    Turn this into practice — try the minor seventh chord in a quick Sonid exercise.

    Turn this into practice — try the dominant seventh chord in a quick Sonid exercise.

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