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Sync settings

Choose what your account keeps in step on every device where you are signed in.

  • My tools

    Always synced: the tools on your board, their order and size.

  • The windows open on your start page, including what you typed in them.

  • Every note in the notepad – on the notepad page, on your board and in windows.

  • Every list of website shortcuts – on the shortcuts page, on your board and in windows.

  • Every grid in the cover grid maker – on its page, on your board and in windows.

  • Every list of bookmarked organisations in the OIN lookup – on its page, on your board and in windows.

  • Keeps your pipeline and saved recipes on all your devices. Your files are never synced – only the steps and settings.

Turning something off removes it from your account straight away. Your devices keep their own copy.

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Tools that can tell you about something new while a Synsi tab is open, even when you are in another tab or app. Choose them for this browser.

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  • Says “New message” while a Synsi tab is open – never who wrote it or what.

Your choice is stored in this browser only. Notifications never show personal content such as a message or a number. They work while a Synsi tab is open; closed tabs get none.

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Unit Converter – Length, Weight, Temperature, Data and More

Convert metric, imperial and US measurements for cooking, automotive, computing, energy and everyday use.

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Result –

Runs in your browser – your data never leaves your device Also available via our free API

How to use the Unit Converter

  1. 1 Choose a category, such as length or temperature.
  2. 2 Enter the value and pick the unit to convert from and to.
  3. 3 Read the result; use the ⇄ button to swap the units.

Precise conversions

Every unit is converted through an exact base unit (metre, kilogram, litre, square metre, metre per second, second or byte) using the official definitions – for example, one inch is exactly 2.54 cm and one pound is exactly 0.45359237 kg. Results are shown with up to 12 significant digits.

Categories

  • Length – millimetres to nautical miles, including inches, feet, yards and miles.
  • Weight – milligrams to tonnes, ounces, pounds and stone.
  • Volume – millilitres, litres and cubic metres, plus US cups, pints, quarts and gallons, and the UK gallon.
  • Area – square metres, hectares, acres, square feet and more.
  • Speed – km/h, mph, m/s, knots and feet per second.
  • Time – milliseconds to years (a year is taken as 365.25 days).
  • Data – decimal units (KB, MB, GB = powers of 1000) and binary units (KiB, MiB, GiB = powers of 1024).
  • Temperature – Celsius, Fahrenheit and Kelvin.

US or UK gallons?

A US gallon is 3.785 litres, while an imperial (UK) gallon is 4.546 litres. The same applies to pints and fluid ounces – choose the right one to avoid errors of about 20%.

Why is my 1 TB drive only 931 GB?

Drive makers use decimal units (1 TB = 10¹² bytes), while many operating systems display binary units (1 TiB = 2⁴⁰ bytes) but label them “GB”. Convert TB to GiB to see the number your computer shows.

Sources

Conversion factors follow the SI definitions in the BIPM SI Brochure and the exact factors for US customary and imperial units in NIST Special Publication 811.

Frequently asked questions

How many centimetres are in an inch?

Exactly 2.54 centimetres.

How do I convert Celsius to Fahrenheit?

Multiply by 9/5 and add 32. For example, 20 °C × 1.8 + 32 = 68 °F.

What is the difference between MB and MiB?

A megabyte (MB) is 1,000,000 bytes; a mebibyte (MiB) is 1,048,576 bytes (2²⁰).

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