Converting a melody into guitar chords

I have only a sketchy knowledge of musical theory and a pretty average musical ear. I am writing a song for a friends 50 th birthday - almost got the words and tune worked out, but no idea how to fit it to a guitar. Any hints or websites that might help?
e.g. if the first note is a G then I should start with a G chord or is that too simple?

That is too simple. There’s a LOT of chords that could go under any given melody and still sound good to Western ears.

If you give me the melody, I can come up with a simple chord chart. What you generally want to do is figure out what key it’s in. If the first note is a “G”, then you may very well be in the key of G. Although C is not an unreasonable guess, either. E-flat’s a possibility, too. E minor, G minor, etc. would all rank up there. My guess is your tune is probably in a major key and probably in G or C. My advice would be to look at what the last note of your melody is–where the tune wants to resolve to. That’s probably the key of your song.

So, if your song is in C, I would try messing around with these chords:

C, F, G(7), Dm, Am

specifically, common progressions will include:
C-F-G-C
C-G-F-C
C-Am-F-G
C-Am-Dm-G
C-Dm-F-G
If it’s in G, try these:

G, C, D(7), Am, Em
G-C-D-G
G-D-C-G
G-Em-C-D
G-Em-Am-D
G-Am-C-D

Those are your best bets for a simple harmonic structure, but the possibilities are pretty much endless.

thnx for the reply. It seems that there is no one “right” answer. In a way that makes me feel better as it means if I come up with a progression that sounds about right to me then it may well be that it will work for everyone else as well.

pulykamell has already posted a nice set of progressions. My own first step would be to try playing the melody on a piano keyboard and then see what notes I am using. From that, the key of the piece will be apparent. If you aren’t familiar with which sharps and flats go with which key, see step 3 here.

I’d probably move my tune up or down on the keyboard until the whole thing was on the white keys, meaning it is in C.

Then you can reach into your bucket of chords for the C, Dm, F, G7, and Am chords mentioned above and do wondrous things. Keep in mind that most early rock was based on 3 chords, I, IV, and V. Hence, C, F, and G7 would be good starts; just make sure it ends on the C chord (G7->C most likely).

And you’re right, if it sounds good then what’s the worry?

No, there definitely is no such thing as a “right” answer. There may be better or worse answers (and that’s subjective, too) depending on what kind of style and feeling you want to effect, but, at the end of the day, if it sounds good, it is good. It’s not unusual for musicians to take a well-known song with an established melody and harmony and change the chords behind the melody (“reharmonize” the tune.)

The only time I’ve run into right or wrong answers is when you are playing something that has already been harmonized by someone else. If it’s on a recording, people will expect the chords to be the same, but that’s usually not that big a deal*. Far bigger is when you are playing in a group. Everyone doesn’t have to use the exact same chords, but they do have to work with one another

*I performed a version of “You Raise Me Up” that was completely different from the original. The singers I was accompanying didn’t even notice the difference. And they were having to harmonize with it.

Since the OP is about The Arts, let’s move from General Questions to Cafe Society.

samclem, Moderator, GQ

I’ve done it many times and know no more music theory than the 1-3-5(Maj7) progression that works with most rock, blues, and folk songs. It’s usually “find the first note that is also in a chord and take it from there.” If that doesn’t work find it in another chord.

Remember that not every note of the melody has to have a chord to go with it.

There’s actually a program called Microsoft Songsmith that does that for you. You record a melody, and it will come up with an accompaniment in a chosen style. Here’s a demo: http://www.youtube.com/watch?v=DaUQ4_kJBHw

Sometimes it doesn’t work so well:

That’s the only one that actually sounds bad. The rest are just inappropriate. And some are kinda catchy.