Convert British Pound Sterling (GBP) to Gibraltar Pound (GIP)

1 british_pound_sterling = 1 british_pound_sterling

Exchange rates last updated: November 12, 2025 16:00

Conversion Formula for British Pound Sterling to Gibraltar Pound

The formula of conversion of British Pound Sterling to Gibraltar Pound is very simple. To convert British Pound Sterling to Gibraltar Pound, we can use this simple formula:

1 British Pound Sterling = 1 Gibraltar Pound

1 Gibraltar Pound = 1 British Pound Sterling

One British Pound Sterling is equal to 1 Gibraltar Pound. So, we need to multiply the number of British Pound Sterling by 1 to get the no of Gibraltar Pound. This formula helps when we need to change the measurements from British Pound Sterling to Gibraltar Pound

British Pound Sterling to Gibraltar Pound Conversion

The conversion of British Pound Sterling currency to Gibraltar Pound currency is very simple. Since, as discussed above, One British Pound Sterling is equal to 1 Gibraltar Pound. So, to convert British Pound Sterling to Gibraltar Pound, we must multiply no of British Pound Sterling to 1. Example:-

British Pound Sterling Gibraltar Pound
0.01 British Pound Sterling 0.01 Gibraltar Pound
0.1 British Pound Sterling 0.1 Gibraltar Pound
1 British Pound Sterling 1 Gibraltar Pound
2 British Pound Sterling 2 Gibraltar Pound
3 British Pound Sterling 3 Gibraltar Pound
5 British Pound Sterling 5 Gibraltar Pound
10 British Pound Sterling 10 Gibraltar Pound
20 British Pound Sterling 20 Gibraltar Pound
50 British Pound Sterling 50 Gibraltar Pound
100 British Pound Sterling 100 Gibraltar Pound
500 British Pound Sterling 500 Gibraltar Pound
1,000 British Pound Sterling 1,000 Gibraltar Pound

Details for British Pound Sterling (GBP) Currency

Introduction : The British Pound Sterling (GBP), symbolized by £, is the official currency of the United Kingdom and its territories. It is one of the oldest currencies still in use and is renowned globally for its stability and influence in international finance. The pound is subdivided into 100 pence and is issued by the Bank of England, as well as by other banks in Scotland and Northern Ireland. Widely traded in foreign exchange markets, it is one of the top global reserve currencies. The pound supports a vast economy, encompassing banking, trade, industry, and services across the UK and abroad.

History & Origin : The history of the British Pound Sterling dates back over 1,200 years, making it one of the world’s oldest continuously used currencies. Originally a unit of weight in Anglo-Saxon England, the pound evolved into a monetary system under various monarchs. It was decimalized in 1971, transitioning from the pounds-shillings-pence system to a simpler base-10 system. Throughout the centuries, the pound has remained a symbol of British economic strength, adapting through periods of empire, war, and modern financial globalization. The Bank of England, established in 1694, became the sole issuer of notes in England and Wales and continues to regulate monetary policy and issue currency today.

Current Use : The British Pound Sterling is the primary medium of exchange within the United Kingdom, used for all forms of economic transactions—from retail and salaries to international trade and investment. It is also used in some British Overseas Territories and crown dependencies. The pound is deeply integrated with digital banking, mobile payment platforms, and cashless systems, yet paper notes and coins are still widely circulated. The currency is crucial for global financial markets and is considered a safe-haven asset. Its widespread use reflects the UK's global economic role and makes it essential for investors, travelers, and businesses operating across borders.

Details of United Kingdom

The United Kingdom (UK), officially the United Kingdom of Great Britain and Northern Ireland, is a sovereign country located off the northwestern coast of mainland Europe. It comprises four nations: England, Scotland, Wales, and Northern Ireland, each with its own distinct cultural identity and devolved governments. London, the capital of both the UK and England, is a leading global city renowned for its finance, arts, and political influence.

Historically, the UK played a dominant role in shaping the modern world through its vast empire, advancements in industry, science, and culture. Today, it remains a major economic power with diversified sectors in finance, manufacturing, healthcare, education, and creative industries. The UK is known for institutions like Oxford and Cambridge universities, the BBC, and its constitutional monarchy led by King Charles III.

Though no longer part of the European Union following Brexit, the UK maintains a significant presence in international affairs through its roles in the G7, NATO, and the United Nations Security Council. Its legal and democratic traditions influence many nations worldwide.

The UK is also rich in natural beauty, with landscapes ranging from the Scottish Highlands and Welsh mountains to the English countryside and Northern Irish coastlines. It attracts millions of tourists each year who come to explore its historic landmarks, royal heritage, and cultural festivals.

Despite modern challenges, the UK continues to thrive as a hub of innovation, diversity, and resilience. Its commitment to freedom of expression, scientific research, and global diplomacy makes it one of the world’s most influential and respected countries.

Details for Gibraltar Pound (GIP) Currency

Introduction : The Gibraltar Pound (GIP) is the official currency of Gibraltar, a British Overseas Territory located at the southern tip of the Iberian Peninsula. Issued by the Government of Gibraltar, the GIP is pegged at par with the British Pound Sterling (GBP) and is used interchangeably with it throughout Gibraltar. The currency features uniquely Gibraltarian designs, showcasing cultural, historical, and royal themes. While it functions within a stable monetary framework due to its link with the GBP, the Gibraltar Pound is a distinct symbol of local identity and autonomy in the region’s financial and political structure.

History & Origin : The history of the Gibraltar Pound is closely tied to the United Kingdom, with Gibraltar adopting the British currency system in the early 18th century following British control of the territory in 1704. Over time, Gibraltar began issuing its own notes and coins, which mirrored the denominations of the British system but featured local imagery and symbols. In 1934, Gibraltar officially pegged its currency to the British Pound at a 1:1 ratio, ensuring parity and confidence in trade. The Government of Gibraltar continues to issue its own legal tender, and though not accepted in the UK, GIP remains a vital part of local commerce and heritage.

Current Use : The Gibraltar Pound is used throughout Gibraltar for all forms of economic activity, including retail, services, and public sector operations. It co-circulates with British Pound Sterling, both accepted as legal tender in the territory. However, Gibraltar-issued currency is typically not accepted in the UK. Local banks, ATMs, and electronic payment systems support GIP transactions, and the currency is actively used in tourism, gaming, and financial services. The fixed 1:1 peg to GBP guarantees monetary stability, while the issuance of distinct Gibraltarian banknotes and coins reinforces cultural pride and administrative independence in the region's economy.

Details of Gibraltar

Gibraltar is a British Overseas Territory located at the southernmost point of the Iberian Peninsula, bordering Spain and overlooking the entrance to the Mediterranean Sea. Known for the iconic Rock of Gibraltar, this small yet strategically important territory covers just 6.7 square kilometers but holds immense historical and geopolitical significance.

Gibraltar has been under British control since 1704, following its capture during the War of the Spanish Succession. It was officially ceded to Britain in the Treaty of Utrecht in 1713. Despite recurring sovereignty disputes with Spain, Gibraltar maintains a strong British identity and local governance, with its own parliament and legal system, though defense and foreign affairs are managed by the United Kingdom.

The territory is a cultural mosaic, blending British customs with Mediterranean and Spanish influences. English is the official language, but Spanish is widely spoken, along with Llanito—a unique local dialect. The population is diverse, with communities of Genoese, Maltese, Indian, and Moroccan descent, contributing to Gibraltar’s rich social fabric and cuisine.

Gibraltar's economy is driven by tourism, online gaming, shipping services, and financial sectors. Its low-tax regime has attracted global businesses, particularly in fintech and insurance. The port serves as a key refueling station and maritime hub due to its strategic location at the crossroads of major shipping routes.

Tourism plays a vital role, with visitors drawn to the Rock of Gibraltar, the Upper Rock Nature Reserve, and its famous Barbary macaques—the only wild monkey population in Europe. With a sunny climate, bustling shopping streets, and historic military tunnels, Gibraltar combines natural beauty and cultural intrigue. It continues to thrive as a unique British enclave at the edge of Europe, embracing modern development while preserving its storied past.

Convert British Pound Sterling to Other Currencies

British Pound Sterling to United Arab Emirates DirhamUnited Arab Emirates Dirham to British Pound Sterling
British Pound Sterling to Afghan AfghaniAfghan Afghani to British Pound Sterling
British Pound Sterling to Albanian LekAlbanian Lek to British Pound Sterling
British Pound Sterling to Armenian DramArmenian Dram to British Pound Sterling
British Pound Sterling to Netherlands Antillean GuilderNetherlands Antillean Guilder to British Pound Sterling
British Pound Sterling to Angolan KwanzaAngolan Kwanza to British Pound Sterling
British Pound Sterling to Argentine PesoArgentine Peso to British Pound Sterling
British Pound Sterling to Australian DollarAustralian Dollar to British Pound Sterling
British Pound Sterling to Aruban FlorinAruban Florin to British Pound Sterling
British Pound Sterling to Azerbaijani ManatAzerbaijani Manat to British Pound Sterling
British Pound Sterling to Bosnia Herzegovina Convertible MarkBosnia Herzegovina Convertible Mark to British Pound Sterling
British Pound Sterling to Barbadian DollarBarbadian Dollar to British Pound Sterling
British Pound Sterling to Bangladeshi TakaBangladeshi Taka to British Pound Sterling
British Pound Sterling to Bulgarian LevBulgarian Lev to British Pound Sterling
British Pound Sterling to Bahraini DinarBahraini Dinar to British Pound Sterling
British Pound Sterling to Burundian FrancBurundian Franc to British Pound Sterling
British Pound Sterling to Bermudan DollarBermudan Dollar to British Pound Sterling
British Pound Sterling to Brunei DollarBrunei Dollar to British Pound Sterling
British Pound Sterling to Bolivian BolivianoBolivian Boliviano to British Pound Sterling
British Pound Sterling to Brazilian RealBrazilian Real to British Pound Sterling
British Pound Sterling to Bahamian DollarBahamian Dollar to British Pound Sterling
British Pound Sterling to Bhutanese NgultrumBhutanese Ngultrum to British Pound Sterling
British Pound Sterling to Botswanan PulaBotswanan Pula to British Pound Sterling
British Pound Sterling to Belarusian RubleBelarusian Ruble to British Pound Sterling
British Pound Sterling to Belize DollarBelize Dollar to British Pound Sterling
British Pound Sterling to Canadian DollarCanadian Dollar to British Pound Sterling
British Pound Sterling to Congolese FrancCongolese Franc to British Pound Sterling
British Pound Sterling to Swiss FrancSwiss Franc to British Pound Sterling
British Pound Sterling to Chilean Unit Of Account UfChilean Unit Of Account Uf to British Pound Sterling
British Pound Sterling to Chilean PesoChilean Peso to British Pound Sterling
British Pound Sterling to Chinese Yuan OffshoreChinese Yuan Offshore to British Pound Sterling
British Pound Sterling to Chinese YuanChinese Yuan to British Pound Sterling
British Pound Sterling to Colombian PesoColombian Peso to British Pound Sterling
British Pound Sterling to Costa Rican ColonCosta Rican Colon to British Pound Sterling
British Pound Sterling to Cuban Convertible PesoCuban Convertible Peso to British Pound Sterling
British Pound Sterling to Cuban PesoCuban Peso to British Pound Sterling
British Pound Sterling to Cape Verdean EscudoCape Verdean Escudo to British Pound Sterling
British Pound Sterling to Czech Republic KorunaCzech Republic Koruna to British Pound Sterling
British Pound Sterling to Djiboutian FrancDjiboutian Franc to British Pound Sterling
British Pound Sterling to Danish KroneDanish Krone to British Pound Sterling
British Pound Sterling to Dominican PesoDominican Peso to British Pound Sterling
British Pound Sterling to Algerian DinarAlgerian Dinar to British Pound Sterling
British Pound Sterling to Egyptian PoundEgyptian Pound to British Pound Sterling
British Pound Sterling to Eritrean NakfaEritrean Nakfa to British Pound Sterling
British Pound Sterling to Ethiopian BirrEthiopian Birr to British Pound Sterling
British Pound Sterling to EuroEuro to British Pound Sterling
British Pound Sterling to Fijian DollarFijian Dollar to British Pound Sterling
British Pound Sterling to Falkland Islands PoundFalkland Islands Pound to British Pound Sterling
British Pound Sterling to Georgian LariGeorgian Lari to British Pound Sterling
British Pound Sterling to Guernsey PoundGuernsey Pound to British Pound Sterling
British Pound Sterling to Ghanaian CediGhanaian Cedi to British Pound Sterling
British Pound Sterling to Gibraltar PoundGibraltar Pound to British Pound Sterling
British Pound Sterling to Gambian DalasiGambian Dalasi to British Pound Sterling
British Pound Sterling to Guinean FrancGuinean Franc to British Pound Sterling
British Pound Sterling to Guatemalan QuetzalGuatemalan Quetzal to British Pound Sterling
British Pound Sterling to Guyanaese DollarGuyanaese Dollar to British Pound Sterling
British Pound Sterling to Hong Kong DollarHong Kong Dollar to British Pound Sterling
British Pound Sterling to Honduran LempiraHonduran Lempira to British Pound Sterling
British Pound Sterling to Haitian GourdeHaitian Gourde to British Pound Sterling
British Pound Sterling to Hungarian ForintHungarian Forint to British Pound Sterling
British Pound Sterling to Indonesian RupiahIndonesian Rupiah to British Pound Sterling
British Pound Sterling to Israeli New SheqelIsraeli New Sheqel to British Pound Sterling
British Pound Sterling to Manx PoundManx Pound to British Pound Sterling
British Pound Sterling to Indian RupeeIndian Rupee to British Pound Sterling
British Pound Sterling to Iraqi DinarIraqi Dinar to British Pound Sterling
British Pound Sterling to Iranian RialIranian Rial to British Pound Sterling
British Pound Sterling to Icelandic KronaIcelandic Krona to British Pound Sterling
British Pound Sterling to Jersey PoundJersey Pound to British Pound Sterling
British Pound Sterling to Jamaican DollarJamaican Dollar to British Pound Sterling
British Pound Sterling to Jordanian DinarJordanian Dinar to British Pound Sterling
British Pound Sterling to Japanese YenJapanese Yen to British Pound Sterling
British Pound Sterling to Kenyan ShillingKenyan Shilling to British Pound Sterling
British Pound Sterling to Kyrgystani SomKyrgystani Som to British Pound Sterling
British Pound Sterling to Cambodian RielCambodian Riel to British Pound Sterling
British Pound Sterling to Comorian FrancComorian Franc to British Pound Sterling
British Pound Sterling to North Korean WonNorth Korean Won to British Pound Sterling
British Pound Sterling to South Korean WonSouth Korean Won to British Pound Sterling
British Pound Sterling to Kuwaiti DinarKuwaiti Dinar to British Pound Sterling
British Pound Sterling to Cayman Islands DollarCayman Islands Dollar to British Pound Sterling
British Pound Sterling to Kazakhstani TengeKazakhstani Tenge to British Pound Sterling
British Pound Sterling to Laotian KipLaotian Kip to British Pound Sterling
British Pound Sterling to Lebanese PoundLebanese Pound to British Pound Sterling
British Pound Sterling to Sri Lankan RupeeSri Lankan Rupee to British Pound Sterling
British Pound Sterling to Liberian DollarLiberian Dollar to British Pound Sterling
British Pound Sterling to Lesotho LotiLesotho Loti to British Pound Sterling
British Pound Sterling to Libyan DinarLibyan Dinar to British Pound Sterling
British Pound Sterling to Moroccan DirhamMoroccan Dirham to British Pound Sterling
British Pound Sterling to Moldovan LeuMoldovan Leu to British Pound Sterling
British Pound Sterling to Malagasy AriaryMalagasy Ariary to British Pound Sterling
British Pound Sterling to Macedonian DenarMacedonian Denar to British Pound Sterling
British Pound Sterling to Myanma KyatMyanma Kyat to British Pound Sterling
British Pound Sterling to Mongolian TugrikMongolian Tugrik to British Pound Sterling
British Pound Sterling to Macanese PatacaMacanese Pataca to British Pound Sterling
British Pound Sterling to Mauritanian OuguiyaMauritanian Ouguiya to British Pound Sterling
British Pound Sterling to Mauritian RupeeMauritian Rupee to British Pound Sterling
British Pound Sterling to Maldivian RufiyaaMaldivian Rufiyaa to British Pound Sterling
British Pound Sterling to Malawian KwachaMalawian Kwacha to British Pound Sterling
British Pound Sterling to Mexican PesoMexican Peso to British Pound Sterling
British Pound Sterling to Malaysian RinggitMalaysian Ringgit to British Pound Sterling
British Pound Sterling to Mozambican MeticalMozambican Metical to British Pound Sterling
British Pound Sterling to Namibian DollarNamibian Dollar to British Pound Sterling
British Pound Sterling to Nigerian NairaNigerian Naira to British Pound Sterling
British Pound Sterling to Nicaraguan CordobaNicaraguan Cordoba to British Pound Sterling
British Pound Sterling to Norwegian KroneNorwegian Krone to British Pound Sterling
British Pound Sterling to Nepalese RupeeNepalese Rupee to British Pound Sterling
British Pound Sterling to New Zealand DollarNew Zealand Dollar to British Pound Sterling
British Pound Sterling to Omani RialOmani Rial to British Pound Sterling
British Pound Sterling to Panamanian BalboaPanamanian Balboa to British Pound Sterling
British Pound Sterling to Peruvian Nuevo SolPeruvian Nuevo Sol to British Pound Sterling
British Pound Sterling to Papua New Guinean KinaPapua New Guinean Kina to British Pound Sterling
British Pound Sterling to Philippine PesoPhilippine Peso to British Pound Sterling
British Pound Sterling to Pakistani RupeePakistani Rupee to British Pound Sterling
British Pound Sterling to Polish ZlotyPolish Zloty to British Pound Sterling
British Pound Sterling to Paraguayan GuaraniParaguayan Guarani to British Pound Sterling
British Pound Sterling to Qatari RialQatari Rial to British Pound Sterling
British Pound Sterling to Romanian LeuRomanian Leu to British Pound Sterling
British Pound Sterling to Serbian DinarSerbian Dinar to British Pound Sterling
British Pound Sterling to Russian RubleRussian Ruble to British Pound Sterling
British Pound Sterling to Rwandan FrancRwandan Franc to British Pound Sterling
British Pound Sterling to Saudi RiyalSaudi Riyal to British Pound Sterling
British Pound Sterling to Solomon Islands DollarSolomon Islands Dollar to British Pound Sterling
British Pound Sterling to Seychellois RupeeSeychellois Rupee to British Pound Sterling
British Pound Sterling to Sudanese PoundSudanese Pound to British Pound Sterling
British Pound Sterling to Swedish KronaSwedish Krona to British Pound Sterling
British Pound Sterling to Singapore DollarSingapore Dollar to British Pound Sterling
British Pound Sterling to Saint Helena PoundSaint Helena Pound to British Pound Sterling
British Pound Sterling to Sierra Leonean LeoneSierra Leonean Leone to British Pound Sterling
British Pound Sterling to Somali ShillingSomali Shilling to British Pound Sterling
British Pound Sterling to Surinamese DollarSurinamese Dollar to British Pound Sterling
British Pound Sterling to South Sudanese PoundSouth Sudanese Pound to British Pound Sterling
British Pound Sterling to Sao Tome And Principe DobraSao Tome And Principe Dobra to British Pound Sterling
British Pound Sterling to Salvadoran ColonSalvadoran Colon to British Pound Sterling
British Pound Sterling to Syrian PoundSyrian Pound to British Pound Sterling
British Pound Sterling to Swazi LilangeniSwazi Lilangeni to British Pound Sterling
British Pound Sterling to Thai BahtThai Baht to British Pound Sterling
British Pound Sterling to Tajikistani SomoniTajikistani Somoni to British Pound Sterling
British Pound Sterling to Turkmenistani ManatTurkmenistani Manat to British Pound Sterling
British Pound Sterling to Tunisian DinarTunisian Dinar to British Pound Sterling
British Pound Sterling to Tongan PaangaTongan Paanga to British Pound Sterling
British Pound Sterling to Turkish LiraTurkish Lira to British Pound Sterling
British Pound Sterling to Trinidad And Tobago DollarTrinidad And Tobago Dollar to British Pound Sterling
British Pound Sterling to New Taiwan DollarNew Taiwan Dollar to British Pound Sterling
British Pound Sterling to Tanzanian ShillingTanzanian Shilling to British Pound Sterling
British Pound Sterling to Ukrainian HryvniaUkrainian Hryvnia to British Pound Sterling
British Pound Sterling to Ugandan ShillingUgandan Shilling to British Pound Sterling
British Pound Sterling to United States DollarUnited States Dollar to British Pound Sterling
British Pound Sterling to Uruguayan PesoUruguayan Peso to British Pound Sterling
British Pound Sterling to Uzbekistan SomUzbekistan Som to British Pound Sterling
British Pound Sterling to Venezuelan Bolivar SoberanoVenezuelan Bolivar Soberano to British Pound Sterling
British Pound Sterling to Vietnamese DongVietnamese Dong to British Pound Sterling
British Pound Sterling to Vanuatu VatuVanuatu Vatu to British Pound Sterling
British Pound Sterling to Samoan TalaSamoan Tala to British Pound Sterling
British Pound Sterling to Cfa Franc BeacCfa Franc Beac to British Pound Sterling
British Pound Sterling to Silver Troy OunceSilver Troy Ounce to British Pound Sterling
British Pound Sterling to Gold Troy OunceGold Troy Ounce to British Pound Sterling
British Pound Sterling to East Caribbean DollarEast Caribbean Dollar to British Pound Sterling
British Pound Sterling to Special Drawing RightsSpecial Drawing Rights to British Pound Sterling
British Pound Sterling to Cfa Franc BceaoCfa Franc Bceao to British Pound Sterling
British Pound Sterling to Palladium OuncePalladium Ounce to British Pound Sterling
British Pound Sterling to Cfp FrancCfp Franc to British Pound Sterling
British Pound Sterling to Platinum OuncePlatinum Ounce to British Pound Sterling
British Pound Sterling to Yemeni RialYemeni Rial to British Pound Sterling
British Pound Sterling to South African RandSouth African Rand to British Pound Sterling
British Pound Sterling to Zambian KwachaZambian Kwacha to British Pound Sterling

FAQ on British Pound Sterling (GBP) to Gibraltar Pound (GIP) Conversion:

What is the Symbol of British Pound Sterling and Gibraltar Pound?

The symbol for British Pound Sterling is '£', and for Gibraltar Pounds, it is '£'. These symbols are used to denote in everyday currency analysis.

How to convert British Pound Sterling(s) to Gibraltar Pound(es)?

To convert British Pound Sterling(s) to Gibraltar Pound(es), multiply the number of British Pound Sterlings by 1 because one British Pound Sterling equals 1 Gibraltar Pounds.
Formula: Gibraltar Pounds = British Pound Sterlings × 1.
This is a standard rule used in conversions.

How to convert Gibraltar Pound(es) to British Pound Sterling(s) ?

To convert Gibraltar Pound(es) to British Pound Sterling(s), divide the number of Gibraltar Pounds by 1, since, 1 British Pound Sterling contains exactly 1 Gibraltar Pound(es).
Formula: British Pound Sterlings = Gibraltar Pound(s) ÷ 1.
It’s a common calculation in conversions.

How many British Pound Sterling(s) are these in an Gibraltar Pound(es) ?

There are 1 British Pound Sterlings in one Gibraltar Pound. This is derived by dividing 1 Gibraltar Pound by 1, as 1 British Pound Sterling equals 1 Gibraltar Pound(s).
Formula: British Pound Sterling = Gibraltar Pounds ÷ 1.
It’s a precise currency conversion method.

How many Gibraltar Pound(es) are these in an British Pound Sterling(s) ?

There are exactly 1 Gibraltar Pounds in one British Pound Sterling. This is a fixed value used in the measurement system.
Formula: Gibraltar Pound(s) = British Pound Sterlings × 1.
It's one of the most basic conversions.

How many Gibraltar Pound in 10 British Pound Sterling?

There are 10 Gibraltar Pounds in 10 British Pound Sterlings. This is calculated by multiplying 10 by 1.
Formula: 10 British Pound Sterlings × 1 = 10 Gibraltar Pounds.
This conversion is helpful for measurements.

How many Gibraltar Pound(s) in 50 British Pound Sterling?

There are 50 Gibraltar Pounds in 50 British Pound Sterlings. One can calculate it by multiplying 50 by 1.
Formula: 50 British Pound Sterlings × 1 = 50 Gibraltar Pounds.
This conversion is used in many applications.

How many Gibraltar Pound(s) in 100 British Pound Sterling?

There are 100 Gibraltar Pound(s) in 100 British Pound Sterlings. Multiply 100 by 1 to get the result.
Formula: 100 British Pound Sterlings × 1 = 100 Gibraltar Pound(s).
This is a basic currency conversion formula.