An ideal enclosure. Three axial families.

See where the
axes resonate.

Calculate the ideal axial-mode frequencies of a rectangular room from its dimensions and your sound-speed assumption. Keep every axis and order, including exact coincidences.

One focused calculatorNo audio or microphoneLocal CSV, text & SVG

Concept sketch only. Rectangular geometry, rigid boundaries.
No sound level, measured response or treatment result is shown.

Build your axial model

fₙ = n × c / (2 × dimension)
Exactly three records per entered order.

01 / ENTER THE MODEL

Inside dimensions

Use one ideal rectangular enclosure. A stepped, open or irregular room does not become rectangular by entering three approximate dimensions.

Dimension unitOne foot =0.3048 m exactly. Unit switches retain each exact physical dimension.

Length (m)Width (m)Height (m)

Each dimension:0.5–100 m equivalent. Positive plain decimals, up to 12 decimal places. These are software bounds, not room-design recommendations.

Sound speed (m/s)Editable example assumption. Range 100–1000 m/s; not an environmental measurement or automatic correction.Maximum axial orderWhole number 1–20 on each axis. For order 3, all 9 records are retained.

Axial modes only: one nonzero mode index at a time. This is an ideal frequency model, not your room's measured response.

Example ready. Calculate to inspect its nine axial records.

02 / IDEAL MODEL · NOT MEASURED

Separate axial records

Length, width and height records stay separate at an exact tie.

Length fundamental
Width fundamental
Height fundamental

Entered sound-speed assumption
Maximum order per axis
Included frequency range
Exact shared-frequency groups

Frequency markers only. Vertical rows separate axes; neither marker size nor height represents pressure, loudness, decay or response amplitude.

Sorted using exact fractions. The decimal column is rounded to at most 6 decimal places. Identical rounded text does not establish an exact coincidence.

Axis / order	Mode label	Hz display	Exact Hz

Tangential and oblique modes are omitted. These frequencies alone do not predict the level you will hear or a useful speaker, EQ or treatment choice.

All calculations run in this browser. No login, audio generation, recording, microphone access or measurement upload is needed. Dimensions and assumptions determine a mathematical model; Roomaxis does not inspect your room. Privacy details.

1. State your assumptions

Choose three internal dimensions and an explicit sound speed. There is no hidden temperature or humidity calculation.

2. Keep the families

Every axial order gets its own labelled record. Exact equal frequencies are identified without deleting any axis.

3. Save the context

Text and CSV exports retain exact dimensions, sound speed, order labels and model limits. SVG exports show frequency positions alone.