Ways to check alignment

Every method has a trade-off

People have aligned cars at home with strings, tape measures and bubble gauges for decades. Here is how the common methods compare, and where Rim Reader fits.

Costs and accuracy for other methods are typical figures for US retail in 2025–2026, from general knowledge, not our measurements. Results depend on the user.
Method	What it measures	Typical cost	Time	Skill	What careful users can expect
Strings or stands strings squared round the car; distance to each rim measured	Each wheel’s toe against the string box; thrust with care. Camber needs a separate gauge.	$20–$100 homemade; $200–$600 for stand kits	30–60 min or more to set up, then re-measure after each change	High: squaring the strings to the car is the hard part	Good to very good when the box is truly square and centred; poor if it isn’t
Toe plates, tape or trammel the distance between the tires, front and back	Each axle’s total toe only. No individual toe, thrust or steer-ahead.	$0–$50 with a tape and a helper; $50–$150 for toe plates	5–15 min	Low to moderate	Readings to about 1/32–1/16 in across a tire, roughly 0.05–0.15° of total toe; tread and sidewall bulges get in the way
Camber gauge bubble or digital angle gauge on the wheel	Camber; with turn plates, some measure caster	$25–$100; $100–$400 with a wheel adapter	5–15 min	Low to moderate; needs a level floor or a zeroed gauge	Bubble about ±0.25°; digital often ±0.1–0.2° on a car, limited by the floor and how the gauge sits
Wheel-mounted laser kits	Toe, sometimes camber, by projecting onto scales	$150–$600	20–45 min	Moderate	Similar to strings when done well; depends on mounting and scale distance
Other phone or gyroscope gauges a phone or sensor in a bracket held on the rim	Toe by gyroscope, camber by gravity; some offer thrust, steer-ahead and caster	Varies; some charge subscriptions or for spec lookups	10–20 min	Moderate; steady, consistent placement is the hard part	Published reviews of tools in this category have reported toe often within about 0.05° of a rack, but camber 0.1–0.4° off
A shop’s alignment rack cameras or sensor heads on a lift	Everything: toe, camber, caster, steering axis inclination, thrust, set-back; factory specs built in; live readout while adjusting	Tens of thousands of dollars to buy; typically $80–$200 for a four-wheel alignment	An appointment; minutes to measure	A trained technician	The reference when calibrated: typically a few hundredths of a degree for toe
Rim Reader your phone in a printed bracket	Each wheel’s toe and the axle totals, steer-ahead, thrust angle against the body, camber with floor correction, cross camber	Pricing will be announced at launch	Calibration a few minutes, then monthly; toe lap about 2¼ min, front toe under a minute (practised user)	Moderate: two-hand hold, prongs on the metal lip	Repeatability in our tests (typical lap-to-lap variation): rear total toe 0.013°, front 0.026°, camber 0.018°. Details

Where Rim Reader differs

Against strings and toe plates: no box to square and no tape to read. Like strings, it gives each wheel’s toe against the rear axle, and steer-ahead, which toe plates can’t. It does need a calibrated phone and bracket.
Against a plain camber gauge: camber is read against the wheel’s own direction, which made it about 3.5 times more repeatable in our tests, and it measures the floor’s slope beside each tire instead of assuming the floor is level.
Against other phone gauges: every wheel is read twice with a lift between, each axle’s drift is measured from repeat visits rather than assumed, the bracket and phone are calibrated together, and the thrust angle is read against the car’s body.
Against a shop rack: a rack is the reference, measures caster and more, and gives a live readout. Rim Reader is for checking and adjusting at home, and it tells you to have the alignment checked by a shop before highway driving.

Which is right for you

If you only need to check total toe once after a tie-rod change, a tape and a helper may be enough. If you want each wheel’s toe, steer-ahead and thrust without setting up strings, and you will measure more than once, that is what Rim Reader is for. After any suspension or steering work, and before highway driving or carrying heavy loads, have a qualified shop check the alignment.

How Rim Reader works · Accuracy