Unit Converter

Flow Rate Converter

Exact volume. Clear elapsed time.

Convert a flow rate

Exact volume and elapsed time.

Flow entry method

Flow value

Nonnegative decimal, scientific value, fraction or mixed number.

From flow unit

To flow unit

Optional constant-flow estimate

Transfer estimate

Estimates assume constant flow. Startup delay, leakage, pressure changes and varying pump output are not modeled. Zero flow cannot determine a finite fill time.

View flow results

Precision and report

Display significant figures

Show exact target ratioShow calculation stepsShow every-unit flow table

Decimal/scientific input allows twenty significant digits, eighty characters and written exponents from negative thirty through thirty. Fractions allow one hundred digits per component and two hundred forty characters per field. Display digits do not add measurement accuracy.

Worked examples

Flow in cubic meters per hour

Q_t=169.901079552\,\frac{\mathrm{m}^{3}}{\mathrm h}

Exact unit factors; only displayed values are rounded. This is volume per time at the stated volume conditions. Standard or actual gas conditions are not inferred.

Flow conversion record

Entered flow

Q_s=100.000000000\,\frac{\mathrm{ft}^{3}}{\mathrm{min}}

Normalized volume flow

Q_{\mathrm{SI}}=0.0471947443200\,\frac{\mathrm m^3}{\mathrm s}

Source-to-target multiplier

k=1.69901079552

Every unit row describes the same volume flow. US liquid gallons and Imperial gallons are separate conventions. Petroleum barrels contain forty-two US liquid gallons. A day means a fixed elapsed interval of twenty-four hours.

Flow in every supported unit

All twenty-five rows remain in complete text and CSV when this visible table is hidden.

The same volume flow in twenty-five named units
Unit convention	Converted flow
Cubic meters per second	$0.0471947443200\,\frac{\mathrm{m}^{3}}{\mathrm s}$
Cubic meters per hour	$169.901079552\,\frac{\mathrm{m}^{3}}{\mathrm h}$
Liters per second	$47.1947443200\,\frac{\mathrm{L}}{\mathrm s}$
Liters per minute	$2831.68465920\,\frac{\mathrm{L}}{\mathrm{min}}$
Liters per hour	$169901.079552\,\frac{\mathrm{L}}{\mathrm h}$
Milliliters per minute	$2831684.65920\,\frac{\mathrm{mL}}{\mathrm{min}}$
Cubic feet per second	$1.66666666667\,\frac{\mathrm{ft}^{3}}{\mathrm s}$
Cubic feet per minute (CFM)	$100.000000000\,\frac{\mathrm{ft}^{3}}{\mathrm{min}}$
US liquid gallons per minute	$748.051948052\,\frac{\mathrm{gal}_{\mathrm{US,liq}}}{\mathrm{min}}$
US liquid gallons per hour	$44883.1168831\,\frac{\mathrm{gal}_{\mathrm{US,liq}}}{\mathrm h}$
Petroleum barrels per day (42 US liquid gallons)	$25647.4953618\,\frac{\mathrm{bbl}_{\mathrm{oil}}}{\mathrm d}$
Cubic meters per minute	$2.83168465920\,\frac{\mathrm{m}^{3}}{\mathrm{min}}$
Cubic meters per day	$4077.62590925\,\frac{\mathrm{m}^{3}}{\mathrm d}$
Milliliters per second	$47194.7443200\,\frac{\mathrm{mL}}{\mathrm s}$
Milliliters per hour	$1.69901079552\times10^{8}\,\frac{\mathrm{mL}}{\mathrm h}$
Microliters per minute	$2.83168465920\times10^{9}\,\frac{\mathrm{\mu L}}{\mathrm{min}}$
Cubic centimeters per second	$47194.7443200\,\frac{\mathrm{cm}^{3}}{\mathrm s}$
Cubic centimeters per minute	$2831684.65920\,\frac{\mathrm{cm}^{3}}{\mathrm{min}}$
US liquid gallons per second	$12.4675324675\,\frac{\mathrm{gal}_{\mathrm{US,liq}}}{\mathrm s}$
US liquid gallons per day	$1077194.80519\,\frac{\mathrm{gal}_{\mathrm{US,liq}}}{\mathrm d}$
Imperial gallons per minute	$622.883545904\,\frac{\mathrm{gal}_{\mathrm{Imp}}}{\mathrm{min}}$
Imperial gallons per hour	$37373.0127543\,\frac{\mathrm{gal}_{\mathrm{Imp}}}{\mathrm h}$
Imperial gallons per day	$896952.306102\,\frac{\mathrm{gal}_{\mathrm{Imp}}}{\mathrm d}$
Cubic feet per hour	$6000.00000000\,\frac{\mathrm{ft}^{3}}{\mathrm h}$
International acre-feet per day	$3.30578512397\,\frac{\mathrm{acre}\!\cdot\!\mathrm{ft}}{\mathrm d}$

Step-by-step flow conversion

1. Normalize the stated flow convention
Divide the exact volume factor by the exact elapsed-time factor. A unit conversion preserves the stated fluid and volume conditions.
$Q_{\mathrm{SI}}=Q_s\frac{f_V}{f_t}=0.0471947443200\,\frac{\mathrm m^3}{\mathrm s}$
2. Convert the normalized flow to the target
Divide the unrounded cubic-meter-per-second quantity by the exact target factor. Significant figures change the display, not the stored arithmetic.
$Q_t=\frac{Q_{\mathrm{SI}}}{f_{\mathrm{target}}}=169.901079552\,\frac{\mathrm{m}^{3}}{\mathrm h}$

What Can You Create?

Compare flow specifications and review measured transfers

Reconcile named flow specifications

Convert a pump, airflow or process rate between SI, metric liquid, customary cubic volume and explicitly named gallon conventions. All eleven original identifiers remain, including CFM and petroleum barrels per day.

Calculate a collected-volume average

Enter a measured collection volume and its positive elapsed interval independently. The report shows normalized quantities before their ratio, keeping an interval average distinct from an instantaneous instrument reading.

Estimate a constant-rate transfer

Estimate volume delivered over an elapsed duration, or time needed to deliver a target volume. The result stays alongside the converted rate and clearly states the constant-flow assumptions.

Flow rate formulas and worked examples

Normalize volume per elapsed time

A flow unit contains both a volume convention and a time convention. Let $f_V$ convert one source volume unit into cubic meters and $f_t$ convert one source time unit into seconds. Their ratio is the factor into SI volume flow. To move into another flow unit, divide the normalized rate by that target unit's SI factor. The exact defined relationships are applied before the selected significant-figure display is produced.

f_Q=\frac{f_V}{f_t},\qquad Q_{\mathrm{SI}}=Q_s f_s,\qquad Q_t=Q_s\frac{f_s}{f_{\mathrm{target}}}

Example: the original hundred-CFM rate

An international foot is exactly $0.3048\,\mathrm m$ , so its cubic volume factor is the cube of that length factor. There are sixty minutes in an elapsed hour. Applying those two relationships converts $100\,\mathrm{ft^3/min}$ into $169.901079552\,\mathrm{m^3/h}$ . That exact numerical model is independent of the rounding used by the display. The value still needs the same actual or reference volume conditions that accompanied the original gas-flow specification.

100\,\frac{\mathrm{ft}^3}{\mathrm{min}}=100(0.3048)^3(60)\,\frac{\mathrm m^3}{\mathrm h}=169.901079552\,\frac{\mathrm m^3}{\mathrm h}

Example: collected volume and average rate

Suppose the collected volume is $10\,\mathrm L$ over an elapsed interval of $30\,\mathrm s$ . Dividing the normalized volume by the interval gives the average rate. Expressed per minute, the result is $20\,\mathrm{L/min}$ . A collection with the same total volume can hide considerable variation during the interval, so this result should not be labeled an instantaneous maximum or used as evidence that a pump maintained that rate at every moment.

Q=\frac{10\,\mathrm L}{30\,\mathrm s}=\frac13\,\frac{\mathrm L}{\mathrm s}=20\,\frac{\mathrm L}{\mathrm{min}}

Example: delivery volume and ideal fill time

At a maintained rate of $10\,\mathrm{L/min}$ , an elapsed duration of $30\,\mathrm{min}$ corresponds to $300\,\mathrm L$ delivered. The same constant rate would need $50\,\mathrm{min}$ to deliver $500\,\mathrm L$ . These are volume-over-time relationships, not a complete model of a filling tank. If the real rate changes with backpressure or pauses during operation, the actual volume or completion time must be determined from that changing behavior.

V=Qt=300\,\mathrm L,\qquad t=\frac{V}{Q}=\frac{500\,\mathrm L}{10\,\mathrm{L/min}}=50\,\mathrm{min}

Why Users Love This Tool

Follow exact volume and time factors before rounding

Numerical relationships you can inspect

Defined volume factors are divided by exact second, minute, hour or fixed-day factors.
Fractions and scientific input retain exact rational source values through normalization.
Zero-flow and collection-time boundaries are explicit, so undefined estimates are not presented as ordinary numbers.

A complete record across output formats

Swap units using the exact result rather than its rounded presentation.
Keep every conversion row and transfer assumption in complete text and CSV, even when hidden on screen.
Use accessible mathematical output, keyboard focus, validated sharing and guarded print actions on desktop or mobile.

Perfect For

Useful for process work, collection measurements and unit practice

Pump and ventilation specifications

Compare volume-flow labels without confusing US and Imperial gallons or treating CFM as an automatic standard-condition gas conversion. Preserve operating conditions from the manufacturer or measurement record.

Timed collection experiments

Review the average rate from a collected volume with independently selected volume and time units. The generated steps document the measurement ratio while leaving uncertainty and instrument calibration to the actual experiment.

Students and technical reviewers

Trace a numerator-volume factor and denominator-time factor through the calculation. Check delivery and filling examples, distinguish flow from speed, and understand why elapsed days are different from calendar-day scheduling.

How It Works

How it works in three quick steps.

State the source flow or collection measurement

Choose direct volume flow or a collected volume divided by its positive elapsed interval. Enter complete nonnegative values and select the explicitly named source volume and time conventions.

Choose the destination and any transfer estimate

Select the target flow unit and display precision. Optionally supply an elapsed duration to estimate delivered volume, or a target volume to estimate fill time at the stated constant rate.

Inspect and retain the calculation record

Review SI normalization, exact factors, generated steps and transfer assumptions. Copy the complete record or LaTeX, download all rows as CSV, share validated settings or print the visible report to PDF.

Download & Print

Keep the volume convention and elapsed interval with the result

Copy the record or LaTeX working

Copy a complete plain-text result or display-delimited LaTeX steps. A validated share URL restores active measurement or direct-flow input, the destination and optional transfer model.

Download all flow rows as CSV

The quoted UTF-8 file contains every flow unit, exact numerical certificates, collection or transfer context and calculation working. Visibility controls shorten the screen report without discarding complete export data.

Print or save the visible report

Choose the browser’s PDF destination to save the selected report sections. Review paper size and scale before saving; turn off the full unit table when you need a compact record. Long exact ratios retain their full digits in copied text and CSV.

FAQ

Frequently Asked Questions

How do I convert cubic feet per minute to cubic meters per hour?

Use the volume factor for an international cubic foot and the elapsed-time factors for minutes and hours. The relationship is

1\,\mathrm{ft^3/min}=1.69901079552\,\mathrm{m^3/h}

. The original hundred-CFM example therefore gives

169.901079552\,\mathrm{m^3/h}

. This changes the numerical unit representation of the stated volume flow. It does not determine whether a gas volume was recorded at actual operating conditions or at some reference temperature and pressure; preserve those conditions from the source specification.

Are US gallons per minute and Imperial gallons per minute equivalent?

No. The US liquid gallon and Imperial gallon have different defined volumes, so the same number of gallons per minute represents different physical volume flows. The menus name both conventions explicitly. Petroleum barrels use the forty-two-US-liquid-gallon definition rather than an Imperial gallon or an unspecified industrial barrel. If a pump label says only GPM, check its documentation before choosing a convention; the converter does not infer the intended gallon from your location or browser settings.

Can the tool derive flow from a volume collected over time?

Yes. Select the collected-volume entry method, supply a nonnegative volume and a strictly positive elapsed collection interval, and choose each unit independently. The tool normalizes both quantities before using

Q=V/t

. The resulting rate is an average across that interval, not a measurement of instantaneous flow or peak output. A zero collection volume gives zero average flow. A zero collection time is rejected because the ratio would be undefined and cannot establish a valid flow measurement.

How do delivered-volume and fill-time estimates work?

Delivered volume uses

V=Qt

for the stated constant flow and elapsed duration. Fill time uses

t=V/Q

when the flow is positive. These calculations are idealized transfer estimates; the tool does not account for leakage, tank geometry, startup delays, pressure-dependent pump curves or a varying rate. Supply a representative maintained rate for your scenario. Zero flow leaves the unit conversion valid but cannot determine a finite fill time, including when an empty target volume would produce an indeterminate ratio.

Does CFM automatically convert between actual and standard gas flow?

No. This page scales named volume and elapsed-time units at the same stated volume conditions. It does not infer a gas, reference state, absolute pressure, temperature or compressibility factor. Actual and standardized gas-volume flows require additional physical information and a specified correction model. Simply changing cubic feet to liters does not supply that missing information. Keep the applicable actual or reference conditions attached to your source and converted value, especially when comparing gas-meter readings or ventilation specifications.

Can I convert volume flow directly into mass flow or fluid speed?

Additional information is required. Mass flow depends on density through

\dot m=\rho Q

, and an average speed in a uniform-flow cross section depends on area through

u=Q/A

. Neither density nor cross-sectional area can be inferred from the unit label alone. This page therefore keeps its outputs as volume per elapsed time. Use an appropriate density or geometry calculation with the relevant material and operating conditions before interpreting a volume-flow result as mass flow or speed.

What numerical inputs and accuracy controls are supported?

Enter complete decimals, scientific notation, ordinary fractions or proper mixed numbers within the documented bounds. Negative physical volume-flow magnitudes, malformed numbers and nonpositive collection intervals are rejected instead of clamped. Exact rational arithmetic preserves the entered numerical model through unit normalization and transfer calculations. You can select three through twelve display significant figures, and an approximation mark identifies a rounded result. This arithmetic precision does not improve meter accuracy or account for the uncertainty of a collected volume or timing measurement.

What do the copy, share, CSV and PDF actions preserve?

Complete copied text and CSV retain the active source interpretation, named units, SI normalization, exact numerator and denominator certificates, every supported flow row, optional transfer inputs and assumptions, and generated working. Hiding a visible table does not remove its records from complete exports. A share link restores canonical validated active settings. PDF output follows visible report choices and uses a compact notice for exact fractions that would exceed readable print width. Retain calibration and physical operating conditions alongside the saved numerical record.

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About This Tool

About this Flow Rate Converter

The Toolarithm Flow Rate Converter represents a stated volume flow in another explicitly named volume-per-time unit. It preserves the original hundred-cubic-feet-per-minute example and its cubic-meter-per-hour destination while expanding the available conventions. Metric liquid rates, customary cubic-volume rates, US liquid and Imperial gallon rates, petroleum barrels and irrigation acre-feet are defined separately. The volume factor and elapsed-time factor are visible in the numerical model, so a rounded decimal shortcut is not mistaken for the underlying unit definition.

Two input methods support different kinds of source evidence. Direct entry starts from an existing flow specification or meter value. Collected-volume entry starts from a measured total and a positive elapsed interval, producing the average rate during that interval. These methods resolve one normalized volume flow before target-unit conversion. A fixed elapsed day means twenty-four hours; calendar dates, daylight-saving changes and variable-length months are outside this time model. The original material, temperature, pressure and volume-reference conditions remain the responsibility of the source record.

Optional transfer estimates are deliberately stated as constant-flow calculations. One estimate multiplies the resolved rate by a chosen elapsed duration to obtain a delivered volume. The other divides a target volume by a positive rate to obtain elapsed filling time. Zero flow retains a valid zero unit conversion but cannot determine a finite fill time. These outputs do not incorporate tank geometry, leakage, operating pauses, varying pump curves or a pressure correction. They are useful numerical checks when their assumptions match the intended transfer.

Exact rational arithmetic connects the defined factors, source values and transfer calculations. Display significant figures affect presentation rather than stored values, and exact-result swapping avoids feeding rounded output back into the conversion. Complete copied text and CSV preserve all unit rows, numerical certificates and active measurement or transfer context. The visible report can be shortened independently for printing, and accessible server-rendered mathematical content remains available before interactive code loads. The purpose is a clear flow-conversion record with understandable conditions and limits, rather than an unsupported claim about real equipment performance.

Editorial Transparency

Who maintains this page

Ownership and review

Written and maintained by the Toolarithm editorial team. No review date is shown without a maintained editorial record. No independent professional review is claimed.

Methodology

Conversion factors are normalized to canonical units and checked in both directions. Exact definitions and offset formulas are preferred over rounded lookup values.

Read the editorial methodology

Dates and sources

Review dates change only after a substantive method or content check.

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