How long will your battery run a dash cam in parking mode?
Battery capacity, the hardwire kit’s cutoff voltage, and what the camera actually draws while it sits there. The draw is the part no spec sheet gives you, so this page only carries draws measured with a meter at the camera, and it tells you when it is guessing.
Parking mode battery calculator
Hours from a rested battery to the hardwire kit’s cutoff, engine off, nothing else drawing
The short version
Hours to cutoff is the usable part of the battery divided by what the camera pulls from the 12 V side. Two of those three numbers are honest guesses unless someone measures them: how much of a car battery is really usable between rested and the kit’s cutoff, and how efficiently the hardwire kit turns 12 V into the camera’s 5 V. This page states both assumptions on the page, lets you change them, and gives the answer as a range rather than a number that looks more certain than it is.
A bracket, not a promiseHow the estimate is built
Four numbers go in and one comes out, and every one of them is labeled on the calculator with where it came from.
Battery capacity is the amp-hour rating off the label. A car battery is rated for a 20 hour discharge to a much lower voltage than any hardwire kit allows, which is why the next number exists.
Usable capacity is the fraction of that rating you actually get between a rested battery and the kit’s cutoff. The default is 60 percent, which is the working assumption my own parking rig uses for its 7 Ah sealed lead-acid battery between 12.7 V rested and an 11.9 V cutoff: 4.2 Ah of 7. It is an assumption, not a measurement. The rig’s runtime-to-cutoff protocol, which would measure it, has not completed a run yet, and a higher cutoff (the 12.2 or 12.4 V settings some kits offer) leaves less of the battery usable than that, not more. Lower the percentage if your kit cuts high, if the battery is old, or if it is cold.
The parking draw is the number nobody publishes and the reason this page exists. A measured preset is a mean read from a USB meter at the camera’s own input over an eight-minute window in parking mode, which sidesteps the second-to-second swing a spot reading carries. If you type a wattage instead, type what a meter at the camera shows, or what the maker’s table gives if it is in watts. If the maker gives amp-hours per 24 hours, use the third option: that is already a 12 V figure, so it needs no conversion.
The conversion from the camera’s 5 V draw to the battery’s 12 V side goes through the hardwire kit’s converter, and nobody publishes its efficiency either. On my bench the measured 5 V draws agreed with a maker’s own 12 V table at any efficiency between about 72 and 90 percent, which is the range a small buck converter lives in, so the calculator runs both ends and gives you the bracket. The kit’s own standing draw is invisible to a meter at the camera and is not in any figure here; it makes every result run a little long.
Then: usable amp-hours, divided by the 12 V current, is hours. A 50 Ah battery at 60 percent is 30 Ah; a camera pulling 3 W at its 5 V input needs 0.26 to 0.33 A from a 12.6 V battery through a 90 to 72 percent converter; 30 Ah over that is 90 to 113 hours. Change any input and the arithmetic follows.
Hardwire kit cutoff voltages
The hardwire kit is the thing standing between parking mode and a car that will not start. Every kit watches the battery voltage and cuts the camera below a threshold; some let you choose it. These are the published figures for the kits on my bench, quoted from their manuals and packaging, not yet measured on the rig.
| Hardwire kit | Cutoff, 12 V system | Cutoff, 24 V system | Delay before it cuts | Output | Source |
|---|---|---|---|---|---|
| COXPAL 3-wire hardwire kit | 11.9 V | 23.9 V | not published | USB, 5 V | COXPAL A17S/A17D user manual, page 16: auto cut-off below 11.9 V on a 12 V system or 23.9 V on a 24 V system |
| VIOFO HK6 hardwire kit | 11.8 V / 12.0 V / 12.2 V / 12.4 V (slide switch) | 23.6 V / 24.0 V / 24.4 V / 24.8 V | cuts after the voltage stays below the set value for 90 plus or minus 10 seconds | USB-C, 5 V 3 A max | VIOFO HK6 packaging and manual, read 2026-09-16: four cutoff points on a slide switch, 4 m cable, reverse-connection protection |
A higher cutoff protects the start and shortens the park. A kit that cuts at 12.4 V is leaving the battery nearly full, so the usable fraction above should come down with it. A kit that holds for 90 seconds below the threshold, as the HK6 states, will ride through a short dip (a door lock, a dome light) rather than cutting on it. What the kits do at the moment of cutoff, whether they restore power as the battery recovers and how far below the stated figure they really trip, is what my rig’s runtime protocol is built to read, and it has not run to a cutoff yet.
Which dash cams have been measured?
Measured and waiting on a review: COXPAL A17D (4 parking configurations, measured 2026-09-18). Those rows unlock the day the review publishes.
A preset on this page means a camera sat on my parking-mode rig, a 7 Ah sealed lead-acid battery feeding the camera’s own hardwire kit through a switch that stands in for the ignition, with a USB meter inline at the camera’s input. Each parking configuration is run in turn, the ignition switch is opened, and the meter’s accumulator is photographed two and ten minutes after the drop. The difference between the two photos is the eight-minute mean, and that is the figure the preset carries, with the evidence folder it came from named beside it.
The rows are gated on the review, not on the measurement. A camera measured before its review publishes is committed to this page’s data file and stays dark until the review is live, the same day, automatically. Nothing here gets ahead of a review.
Normal recording draws for context, and the storage side of parking mode (a continuous parking mode can fill a card in a day), live in the storage calculator. If you are choosing the card that has to survive a long park, the SD card picker is the one to open.
What this cannot tell you
Whether the camera stays in parking mode that long. A camera can end a park on its own: a guard-time setting, a stationary timer, a thermal limit on a hot day. The calculator assumes the draw continues until the kit cuts, and a camera that ends the park early on its own is a finding for its review, not something this arithmetic can see.
Anything the car itself draws. Alarm, keyless entry, telematics, a trunk light that stays on. The calculator is the camera alone. A parked car’s own standing draw is often as large as the camera’s and comes off the same battery.
The battery’s real state. A five-year-old battery, a cold night, or a short drive that never fully recharged it all shrink the usable fraction below the default, and none of them shows on the label.
Alternator time. The estimate starts from a rested battery with the engine off. It does not model a camera that spends part of its life on a running car, and it does not add anything back for a start in the middle of the park.
What has not been measured yet. The usable fraction, the kit’s converter efficiency and its quiescent draw, and the cutoff’s real trip point are all assumptions or published figures on this page today. The rig’s runtime protocol replaces them one at a time as it runs, and the page updates from the same data file.
Common questions about dash cam parking mode and batteries
How long will a car battery run a dash cam in parking mode?
Take the usable part of the battery and divide it by the camera's 12 V draw. With the assumptions this page states, a 50 Ah battery at 60 percent usable gives 30 Ah, and a camera drawing 3 W at its 5 V input pulls about 0.26 to 0.33 A from the 12 V side through the hardwire kit, so the kit's cutoff arrives after roughly 90 to 113 hours. A camera drawing twice that halves the time, a kit that cuts at a higher voltage shortens it further, and the car's own standing draw comes off the same battery.
What voltage should I set the hardwire kit cutoff to?
The kits on my bench publish cutoffs between 11.8 and 12.4 V on a 12 V system (23.6 to 24.8 V on 24 V). A higher setting leaves more charge for starting and gives a shorter park; a lower one does the opposite. If the car is driven daily and starts easily, the lowest setting the kit offers is the usual choice; if it sits for days, or the battery is old or the weather is cold, set it higher and accept fewer hours.
Does time-lapse parking mode use less power than continuous recording?
Not necessarily, and the only way to know is a meter at the camera. Some cameras keep the whole full-resolution pipeline running in time lapse and simply keep one frame in thirty, which can cost more power than a continuous low-resolution mode that turns the sensor path down. Time lapse always saves card space; whether it saves battery depends on the camera, which is why this page carries measured presets rather than a rule of thumb.
Why does the calculator give a range instead of one number?
Because a draw measured at the camera's 5 V input has to pass back through the hardwire kit's converter to become a 12 V current, and nobody publishes that converter's efficiency. On my bench the measured 5 V figures agreed with a maker's own 12 V table anywhere between about 72 and 90 percent efficiency, so the calculator runs both ends. A figure typed as amp-hours per 24 hours is already a 12 V number and gives a single answer.
Will parking mode drain my battery so the car will not start?
That is the hardwire kit's job to prevent: it cuts the camera when the battery falls to its threshold, which is set above the point where starting becomes doubtful. The risk comes from what the kit cannot see, an old battery whose usable capacity is far below its label, a cold night, or a car whose own standing draw continues after the camera is cut. A higher cutoff setting is the lever if starting matters more than hours.
Where these measurements come from
The parking rig is documented as CKB-BENCH-001: a 7 Ah sealed lead-acid battery through a fuse to the camera’s own hardwire kit, a switch on the ACC line, a Bluetooth battery monitor logging the rail, and a USB power meter inline at the camera. Its runtime protocol drains the battery to the kit’s cutoff per parking mode and reads the cutoff voltage off the log; its transition protocol drops the ignition live and watches what the camera does. The presets on this page are the meter’s accumulator means from those sessions, and every one names its evidence folder. The same rig’s draw tables feed the camera reviews, so a number here and a number in a review can never disagree.