PriceHover

PriceHover

Hover any price on any page and read it in your own currency.
Chrome and Firefox, MV3, built with WXT and Svelte 5.

Release License Stars Browser WXT Svelte Firefox Add-ons

Hovering a yen price on a shop page opens a card with the amount in euros, dollars and pounds. A click on a row copies it, then a price range converts as one range.

Install · What it reads · Inline mode · Crypto · Popup · Privacy

Why

A price in a currency you do not think in costs a tab, a search box and your place in the page. PriceHover reads it where it sits. No account, no paste, one request a day for the rates.

Features

[!NOTE] 2.0.0 changed how $ is read. On a country domain it now converts as that country’s dollar, not as USD. Settings → Behaviour → Read $, kr and ¥ from the site puts the old reading back, except on sites you locked.

What it reads

The same $49.99, two shops

The same $49.99 on a .com shop and on a .ca shop: 44 euros on the first, 31 on the second, with a note that the currency was read from the site

The country comes from the domain, or from the region in <html lang> when the domain says nothing. Vanity endings (.co, .io, .ai, .me, .tv, .to) are ignored, because the country in them means nothing. When the site decided and not the price, the card says so.

One table, eight currencies, three symbols

A regional price table with inline mode on: three dollar rows, two yen rows and three krone rows, each converted from the currency its row names

Two things outrank the domain: a code printed beside the price ($49 CAD), and the row the price sits in, so SteamDB’s ¥ 69 on the Chinese Yuan row is yuan while the ¥ 1,980 on the Japanese Yen row stays yen. One thing ranks below it: what the site’s own pages said, remembered per site on your machine and listed in the settings, where each entry can be removed. A lock you set yourself beats all of them.

On the page Read as
¥74,800 on a .jp shop 74 800 JPY
¥74,800 on a .cn shop 74 800 CNY
$49.99 CAD anywhere 49.99 CAD
¥ 69 on a row labelled Chinese Yuan 69 CNY
₹1,49,900 149 900 INR (Indian lakh grouping)
KD 12.500 12.500 KWD (three decimals, not thousands)
€10-20 a range, 10 to 20 EUR
try 100 times, requires PHP 8.2, error code 500 KD nothing

Inline mode

A product page where every yen amount is followed by its euro equivalent in brackets

Off by default. The site’s own text is never rewritten, only appended to, and text fields, editable areas, code and pre are left alone.

Crypto, both ways

Left, a licence priced 0.0042 BTC read as euros, dollars and pounds. Right, a $49.99 backpack read in euros, pounds, bitcoin and ether.

Off by default. One switch in the settings turns it on, your browser asks for api.coingecko.com, and from then on:

Switching it off hands the permission back, and nothing contacts the second host again.

The popup is also a converter

The PriceHover popup twice: converting 250 CHF, then 0.5 BTC, into a list of currencies

Type 250 chf, 20 usd jpy, 0.5 btc once crypto is on, or a bare number to convert from your own currency. The footer says how old the rates are and refreshes them on demand.

Settings

The PriceHover settings page: currencies, behaviour, sites with paused, locked and remembered entries, about

Your own currency, the list to convert into and its order, hover delay, rounding, inline mode, paused sites, locked site currencies, and the currencies read from each site.

Privacy

PriceHover contacts exactly one host, open.er-api.com, and asks it one question: today’s exchange rates. That request carries nothing about you or the page you are on. Prices are detected on your machine, flags are bundled in the extension, and there is no analytics, no telemetry and no identifier. Two permissions, storage and open.er-api.com, plus the page access every content script needs to read the page it runs on.

Turning on crypto conversion adds a second host, api.coingecko.com, and nothing else. It is off by default, your browser asks before granting it, and switching it back off hands the permission back.

Full details in the privacy policy.

Install

Build from source

bun install
bun run dev            # Chrome, hot reload
bun run build          # Chrome MV3  -> .output/chrome-mv3
bun run build:firefox  # Firefox MV3 -> .output/firefox-mv3
bun test               # unit tests, plus DOM tests under happy-dom
bun run typecheck      # tsc --noEmit, kept clean and enforced in CI

bun run icons, bun run flags and bun run locales regenerate committed files and never run at build time. A release is cut by pushing a vX.Y.Z tag: CI refuses a tag that disagrees with package.json, builds both targets and attaches the zips.

Contributing

Issues and pull requests are welcome. Keep bun test and bun run typecheck clean, and never add a runtime request to a second host. Detection is the part that breaks quietly: a token accepted one position too freely turns error code 500 KD into a price, so every new one arrives with the case that must stay silent.

License

GNU General Public License v3.0 or later. Use it, read it, fork it. Distributing a modified version, publishing a fork to a browser store included, means releasing its source under the same license. Every dependency is GPL-compatible, and only Svelte (MIT) ships inside the extension.