RT60 Reverberation Time Calculator
Reverberation time per octave band (125 Hz – 4 kHz), using both the Sabine and Eyring
formulas, from your room and its surfaces. Compare against the target range for your use.
Units metres feet
Use-case (target) Mixing / critical listening Voice-over / podcast Home theatre Recording live room Office / conference
Surfaces Floor
Ceiling
Walls (all four)
Additional surfaces (windows, doors, added panels) — area replaces wall area Copy shareable link Print
Concrete block, painted Concrete block, unpainted Brick, unglazed Plaster on masonry Gypsum board (12 mm on studs) Marble or glazed tile Cork tiles, 25 mm, on solid backing Concrete or terrazzo floor Vinyl / linoleum on concrete Wood floor on joists Parquet on concrete Carpet, thin, on concrete Carpet, medium, on felt underlay Carpet, heavy, on foam pad Area rug, medium pile, on hard floor Rubber / PVC sports floor tile Ordinary window glass Heavy plate glass Plywood panel (10 mm, air gap) Wood paneling on battens Solid wood door OSB / chipboard panel (10 mm, air gap) Hardboard (3 mm) on battens, air gap Curtains, lightweight, draped Curtains, heavy, deep folds Upholstered seat, fabric, empty Upholstered seat, leather, empty Mattress, bare Filled bookshelf Audience, occupied upholstered seats (per m²) Wooden chairs, unoccupied (per m²) Mineral wool, 50 mm, on wall Mineral wool, 100 mm, on wall Mineral wool, 50 mm, 50 mm air gap Rigid fiberglass 703, 25 mm Rigid fiberglass 703, 50 mm Rigid fiberglass 703, 100 mm Open-cell acoustic foam, 50 mm Open-cell acoustic foam, 25 mm Convoluted egg-crate foam, 50 mm Mineral wool, 150 mm, on wall Polyester acoustic batt, 50 mm Wood-wool cement board, 25 mm Acoustic plaster, sprayed (~25 mm) Fabric-wrapped panel, 50 mm Fabric-wrapped panel, 100 mm Fabric panel, 50 mm + 100 mm gap PET felt panel, 12 mm PET felt panel, 24 mm (double layer) Perforated wood panel + backing Broadband corner trap (300 mm) Superchunk corner (mineral wool) Tuned membrane trap (~60 Hz) Cylindrical tube trap (corner, ~280 mm) Mineral-fiber ceiling tile (15 mm) Suspended acoustic tile + plenum Gypsum board ceiling Plaster ceiling Person, seated (per m² of audience) Adult, standing (per person, sabins) Sabine vs Eyring
Use Sabine for untreated or lightly-treated rooms (mean absorption
below ~0.2). Use Eyring for treated studios and any room with
significant absorption — Sabine over-predicts in those cases. Both formulas and the
constant 0.161 are documented on the methodology page .
Coefficients come from the material database .