48 Fun Facts About WhatsApp

WhatsApp's two founders, Jan Koum and Brian Acton, had both previously worked at which internet company?

Yahoo: Koum joined as an infrastructure engineer in 1997 and worked alongside Acton there for nine years; both left in 2007 and took a year off before starting WhatsApp.

What color do WhatsApp's two check marks turn once the recipient has read a message?

Blue: WhatsApp added read receipts in November 2014, turning the double grey ticks blue once a message is read; one grey tick means sent and two mean delivered.

What was WhatsApp originally designed to do before it became a messaging app?

When Apple launched push notifications in June 2009, users began pinging each other with jokey custom statuses like 'I woke up late', and it turned into instant messaging almost by accident.

How much seed funding did Brian Acton raise for WhatsApp from five former colleagues in 2009?

$250,000: Acton persuaded five former colleagues to invest that sum in October 2009 and formally joined WhatsApp as a co-founder on November 1 that year.

Which company made multiple offers to buy WhatsApp in 2010, all of which were declined?

WhatsApp for Android had only launched in August 2010, after Symbian in May and BlackBerry earlier that year.

Which venture firm, via partner Jim Goetz, bought over 15% of WhatsApp in April 2011?

Sequoia Capital paid about $8 million for more than 15% of WhatsApp in April 2011; its roughly $60 million total investment was worth about $3 billion when Facebook bought the company in 2014.

In February 2014, a year after a funding round valued it at $1.5 billion, Facebook agreed to buy WhatsApp for how much?

$19 billion was then the largest acquisition of a venture-backed company: $4 billion in cash, $12 billion in Facebook shares and $3 billion in restricted stock for the founders and employees.

How many staff did WhatsApp have in February 2013, already one of the world's biggest messaging services?

WhatsApp had about 50 employees in February 2013 while serving roughly 200 million active users; that month Sequoia put in another $50 million at a $1.5 billion valuation.

Which research app that Facebook used to monitor competitors' usage influenced its decision to buy WhatsApp?

Onavo, a VPN and analytics app Facebook bought in 2013, showed WhatsApp's messaging volume far exceeding Messenger's in key markets; that data helped push Facebook to buy WhatsApp in 2014.

How much was the annual subscription fee that WhatsApp announced it was dropping in January 2016?

$1 a year: Koum said the fee was a barrier for users without payment cards, and when WhatsApp dropped it in January 2016 he promised the app would not carry third-party ads.

How much did the European Commission fine WhatsApp's parent in May 2017 for misleading takeover information?

€110 million: Facebook had told the Commission in 2014 that automatically matching WhatsApp and Facebook accounts was technically impossible, then began linking user data in 2016, prompting the fine.

Brian Acton left WhatsApp in September 2017 to fund a nonprofit behind which rival messaging app?

The Signal Foundation's app uses the same encryption protocol WhatsApp had adopted; Acton explained his exit in a Forbes interview a year later.

Who was named as Jan Koum's replacement after he announced his departure as WhatsApp CEO in April 2018?

Chris Daniels, previously head of Facebook's Internet.org, was named WhatsApp's new head in May 2018; Will Cathcart replaced him less than a year later, in March 2019.

How many monthly active users did Meta say WhatsApp had reached in 2025?

3 billion: in 2025 Meta said WhatsApp had passed three billion monthly active users, after crossing one billion in February 2016 and two billion in February 2020.

WhatsApp's end-to-end encryption uses a protocol developed by which organisation?

Open Whisper Systems, the group behind the Signal Protocol, announced its partnership with WhatsApp on November 18, 2014; full end-to-end encryption across every message type was completed in 2016.

WhatsApp is built on a customised version of which open messaging standard?

XMPP: WhatsApp runs a stripped-down binary variant nicknamed FunXMPP, and each account's Jabber ID is its phone number followed by @s.whatsapp.net.

What do users scan with their phone to log in to WhatsApp Web, which launched in January 2015?

A QR code shown at web.whatsapp.com is scanned by the phone's app; at launch the phone had to stay online for the browser session, a requirement dropped with multi-device support in 2021-23.

In which year did WhatsApp add voice calls between two accounts?

2015: WhatsApp rolled out voice calling to Android in early 2015 and to iPhone that April; by June 2016 it reported over 100 million calls a day, and video calls followed in November 2016.

Which audio codec does WhatsApp use for its voice calls?

Opus: WhatsApp's calls use the open Opus codec at 8–16 kHz sampling rates, combining MDCT and linear predictive coding to stay intelligible on poor connections.

WhatsApp's Status feature, launched on February 24, 2017, mimicked the 'stories' of which two other apps?

Snapchat and Facebook stories were the template; Status later gained Voice Status Updates, letting people share voice notes as their status.

When WhatsApp let users edit sent messages in May 2023, how long was the editing window?

15 minutes: WhatsApp introduced message editing in May 2023 with a 15-minute window after sending; edited messages carry an 'edited' label and recipients are not notified of the change.

In May 2022, WhatsApp raised its file upload limit from 100 MB to what?

2 GB: the May 2022 update raised the per-file limit from 100 MB to 2 GB at a stroke and added a progress counter so senders could track large uploads.

What is the maximum number of participants in a WhatsApp video call after the June 2024 improvements?

32: the June 2024 update raised video calls to 32 participants on every device, added audio to screen sharing and a new codec for reliability; larger groups can use the separate voice-chat feature instead.

How long can a WhatsApp video message, introduced in July 2023, last?

60 seconds is the cap; like voice messages, video messages are recorded straight into the chat without saving anything to the phone's gallery.

In which two countries did WhatsApp Channels first launch in June 2023?

Colombia and Singapore were the June 2023 launch markets for Channels; unlike chats and groups, channel broadcasts are not end-to-end encrypted, and the feature went global in September 2023.

Which three countries first got WhatsApp's third-party animated stickers in March 2021?

Sticker support itself dates from October 2018, and unusually WhatsApp requires third-party apps to add sticker packs.

On November 30, 2015, WhatsApp's Android app made links to which rival service unclickable?

Telegram: from November 30, 2015 links to telegram.me were rendered unclickable in WhatsApp's Android app; several outlets confirmed it was intentional, and critics called the move anti-competitive.

Which Israeli surveillance firm did WhatsApp sue in 2019 over spyware injected via voice calls?

NSO Group's Pegasus exploit could infect a phone through a call the target never answered, hitting at least 1,400 users in 20 countries; WhatsApp sued in a San Francisco court in October 2019.

On which 2016 date did WhatsApp announce end-to-end encryption for all communication on the app?

April 5, 2016: WhatsApp announced that day that end-to-end encryption now covered every message, call and file on all platforms; a year earlier Heise had shown only Android-to-Android texts were encrypted.

In which two countries did WhatsApp Pay first become generally available for peer-to-peer transfers?

India and Brazil: in India WhatsApp Pay runs on the UPI system and launched in November 2020 under a 20-million-user cap; in Brazil the central bank suspended it in June 2020 and it relaunched in May 2021.

Which country is by far WhatsApp's largest market by number of users?

India passed 200 million monthly users in February 2017, and WhatsApp added forwarded-message labels after misinformation there led to lynchings.

In September 2017, security researchers reported WhatsApp completely blocked in which country?

China later had Apple remove the app from its App Store there, in April 2024, citing government orders on national security grounds.

In May 2016, a court order forced mobile providers in which country to block WhatsApp for 72 hours?

Brazil: a judge in Sergipe ordered carriers to block WhatsApp for 72 hours on May 2, 2016 over its refusal to hand over user data in a drug case; the block was lifted on appeal within a day.

Which country's army banned WhatsApp in December 2021, telling personnel to use the home-grown Threema instead?

Switzerland: the Swiss army told personnel to switch to the Swiss-made Threema, citing concern that U.S. authorities could reach WhatsApp data under the CLOUD Act.

Which country briefly banned WhatsApp in 2016 after the Russian ambassador was assassinated there?

Turkey: after Russian ambassador Andrei Karlov was shot dead in Ankara on December 19, 2016, Turkish authorities briefly throttled WhatsApp, Facebook, Twitter and YouTube.

Which two organisations did WhatsApp partner with in March 2020 to run COVID-19 information hotlines?

The World Health Organization and UNICEF both launched WhatsApp hotlines in March 2020 to share verified COVID-19 information, and the same month WhatsApp began testing tools to check the context of forwarded messages.

Where did WhatsApp's January 2021 privacy-policy update not apply, because it breached local data-protection rules?

The EU's GDPR principles were violated by the policy; WhatsApp postponed the update to May 15, 2021 and said it would not cut off users who declined the new terms.

Which EU law forced Meta in March 2024 to let third-party apps interoperate with WhatsApp?

The Digital Markets Act: its March 2024 compliance deadline obliged WhatsApp, as a designated gatekeeper service, to open up to third-party messaging apps, with end-to-end encryption required to be preserved.

How many messages a day was WhatsApp handling in August 2012?

10 billion: WhatsApp passed 10 billion messages a day in August 2012, up from one billion a day in late 2011; the Financial Times said it had done to SMS what Skype did to landline international calls.

WhatsApp was ranked in which position among the most downloaded mobile apps of the decade 2010-2019?

Third: App Annie's December 2019 decade rankings put WhatsApp behind only Facebook and Facebook Messenger for downloads in 2010–2019, with Instagram fourth and Snapchat fifth.

In which city was WhatsApp co-founder Jan Koum born?

Kyiv: Koum was born there in 1976 and grew up in nearby Fastiv before emigrating with his mother and grandmother to Mountain View, California, at 16, where he swept a grocery store's floors.

Which company rejected both Jan Koum and Brian Acton when they applied after leaving Yahoo?

Facebook turned down both men: Acton tweeted about his rejection in August 2009, after the pair had spent a year travelling South America and playing ultimate frisbee.

Which two future Napster creators did Jan Koum meet through the computer security think tank w00w00?

Shawn Fanning and Jordan Ritter, who went on to build Napster, were fellow members of the w00w00 security group Koum joined in the 1990s while working as a security tester at Ernst & Young.

On which date did WhatsApp become officially supported on the iPad?

May 27, 2025: WhatsApp released its first official iPad app that day; like the web, Windows and Mac versions it works as a linked device that syncs with the phone.

Where did Koum's friend find Igor Solomennikov, the developer who built the first iPhone version?

RentACoder.com: Koum's friend Alex Fishman found Russian developer Igor Solomennikov on the freelancing site; the earliest users were a handful of Fishman's friends in San Jose.

When WhatsApp raised its file limit to 2 GB in May 2022, the maximum group size grew to how many members?

512: the May 2022 update doubled the group cap from 256 to 512 members; the limit was raised again to 1,024 in November 2022 alongside the Communities feature.

Whose phone was hacked via a malicious WhatsApp file sent from the Saudi crown prince's account?

Jeff Bezos: a forensic report made public in January 2020 found his phone was likely compromised by a video file sent from Mohammed bin Salman's WhatsApp account in May 2018; UN rapporteurs called for an investigation.

When WhatsApp first let users delete messages sent by mistake in November 2017, how long was the window?

Seven minutes: 'Delete for Everyone' initially allowed unsending within seven minutes; the window was later stretched to just over an hour in 2018 and to two days in 2022.