Spectra may refer to:

• The plural of spectrum, conditions or values that vary over a continuum, especially the colours of visible light
• Spectra (journal), of the Museum Computer Network (MCN)
• The plural of spectrum (topology), an object representing a generalized cohomology theory in algebraic topology
• Spectra, an association of LGBT mathematicians
• Spectra, an order of stick-insects, or Phasmatodea