Free · No sign-up · Nothing leaves your browser

Stop converting units in your head.

Hover over any measurement on any web page and the conversion appears instantly — no clicks, no pop-ups, no math. It even decodes specs like USB-C power and battery capacity.

60+ units, 12 categories
0 bytes collected
1-click install
28V @ 5A
PD 3.1 EPR
shop.example.com / 140w-power-bank
Hover the underlined specs ↓
140W GaN Power Bank
★★★★★ 4.8 · 2,317 reviews
$89.99
Capacity20,000mAh20 Ah· capacity Li-ion Max output140W28V @ 5A· PD 3.1 EPR USB-C Dimensions250×110mm9.84 × 4.33 in Weight560g1.23 lb Display1.5″38.1 mm OLED
Not just a unit converter

It understands what you're reading.

Most converters do mm → inches and stop. Hover Measure reads the context around a number — so a charger's wattage becomes a real charging spec, and a battery's mAh stays a capacity, not a meaningless energy figure.

140W28V @ 5A

Recognizes USB-C Power Delivery and shows the real charging profile (PD 3.1 EPR) — not 0.19 horsepower.

20,000mAh20 Ah

Knows battery capacity is capacity. Converts to amp-hours, not joules.

250×110mm9.84 × 4.33 in

Reads whole dimension strings and converts every value in a single hover.

60+ units, everywhere you read

If it's a measurement, you can hover it

From everyday shopping to deep spec sheets — twelve categories, converted the instant your cursor lands.

Length
250 mm 9.84 in
Weight
2 kg 4.41 lb
Volume
500 ml 16.9 fl oz
Temperature
200 °C 392 °F
Area
50 ft² 4.65 m²
Speed
100 km/h 62.1 mph
Pressure
35 psi 2.41 bar
Power
1500 W 2.01 hp
Energy
500 kcal 2,092 kJ
Data
64 GB 65,536 MB
Capacity
20,000 mAh 20 Ah
USB-C PD
140 W 28V @ 5A
Built to disappear

Everything you need, nothing you don't

Works on any site

Amazon, AliExpress, eBay, spec sheets, blogs — if it has a measurement, you can hover it.

Smart context

Reads USB-C power, battery capacity and dimensions — not just raw unit math.

Private & offline

Every conversion runs locally. No account, no tracking, nothing leaves your browser.

Your precision

Pick 0–3 decimal places and see exactly the level of detail you want.

Every unit type

Length, weight, volume, temperature, area, speed, pressure, power, data and more.

Zero friction

No clicks, no pop-ups, no copy-paste. Hover to see it, move on with your day.

The difference

Why people switch to Hover Measure

Hover MeasureTypical converter
Convert on hover — no clicksCopy, paste, or type it in
Works inline on any web pageSeparate tab or popup
Understands specs (USB-PD, mAh) raw numbers only
Nothing leaves your browserOften ad-funded / tracked
PriceFreeFree with ads — or paid
Setup1 clickBookmark or search each time
Three steps

Hover. See. Done.

1

Add to Chrome

One click to install. Free, no account, no setup screens.

2

Browse normally

Hover Measure quietly underlines measurements as you read.

3

Hover anything

Point at a spec and the conversion appears — instantly, in place.

Built for spec-readers

Made for people who shop by the numbers

If you compare gear across international listings — chargers, monitors, drones, 3D-printer parts, car parts, tools — the specs are in foreign units half the time. Hover Measure makes them make sense at a glance.

Electronics & chargers Makers & 3D printing RC & drones Automotive & mechanics Tools & hardware Importers & resellers Engineers Home & DIY
Good to know

Questions, answered

Is it really free?+

Yes — the core extension is free, with no account required. We may add an optional Pro tier later, but converting on hover stays free.

Does it collect my data?+

No. Every conversion runs locally in your browser. Hover Measure makes no network calls and has no analytics or tracking.

What sites does it work on?+

Any site. It reads the text on the page, so it works on marketplaces, spec sheets, articles and forums — anywhere measurements appear.

Which units are supported?+

Length, weight, volume, temperature, area, speed, pressure, power, energy, data, battery capacity, and smart specs like USB-C Power Delivery.

Will it slow down my browsing?+

No. It's lightweight, runs locally, and is carefully scoped inside its own shadow DOM so it never touches a page's own layout or styles.

Stop converting units in your head.

Add Hover Measure to Chrome and never do mental math on a product page again.

Add to Chrome — Free