Ask.
Get the answer.

Type the whole expression, with brackets if you like, and the answer appears as you type.

The same expression engine as the basic one, with trigonometry, logarithms, powers and constants.

Type a function of x and the curve is drawn straight away. Set the range below the field.

Enter the coefficients and the equation is solved, with the discriminant and vertex thrown in.

Enter three of the six measurements, at least one of them a side, and the rest are worked out.

Pick a shape, enter the measurements, and area and perimeter appear straight away.

Pick a solid, enter the measurements, and volume and surface area appear straight away.

Enter two points in the plane and the distance, midpoint and equation of the line are worked out.

Three common percentage questions, each with its own answer. Type your numbers and the result updates as you go.

Type in either field and the other fills in. The fraction is reduced automatically.

Choose decimal places or significant figures, and the result appears under each of the common rules.

Type the number in the base you are starting from, and it appears in all the common bases at once.

Type in either field and the other fills in. Works for the numbers 1 to 3,999,999.

Paste your numbers, one per line or separated by commas, and the whole summary is worked out.

Enter a number and it is broken into primes. Further down are the highest common factor and the lowest common multiple.

Enter two fractions and choose an operation, and the answer appears reduced with the working below.

Choose the range and how many, and the numbers are drawn with randomness nobody can predict.

Choose how many dice and how many sides, then roll.

Pick a preset or set up the cup yourself, and roll. Your phone replaces the dice; you keep score as usual.

One press, heads or tails, exactly half each.

Paste the list, choose how many to draw, and draw.

Convert between probability, decimal odds, fractional odds and American odds.

Choose the cards in one suit for you and dummy in bridge to see how to play the suit for as many tricks as possible, and how good the chances are.

Choose the cards to see how often your hand wins, how many outs you have and whether a call pays.

Choose your hole cards, the board and your opponents’ hands to see what share of the pot each hand takes.

Choose the cards to see your winning chance in short deck, played with sixes to aces only.

Choose your cards and the cards you can see in front of your opponents to see how often each hand wins at showdown.

Choose your hand to see which cards to hold and how often the draw makes the hand you are aiming for.

Choose the table rules to see the best play for every hand against the dealer’s card and how much the house wins in the long run.

Choose the wheel to see the payout, the chance of winning and the house edge for every bet.

Choose the number of decks to see how often banker, player and tie win and what each bet costs.

See the payout, the chance of winning and the house edge for every craps bet, and how free odds lower the edge on the line bets.

Click the board to set up the position and see how many of the 36 rolls hit, and which ones.

Enter the pip counts in a race with no contact to see your winning chance and whether to double and take.

Choose an amount, a measure and an ingredient to see what it weighs and how much it is in other measures.

Enter height and weight, and the body mass index is worked out.

Enter a size or the length of the foot, and the equivalents in the other systems appear.

Pick a unit and a quantity, and it is converted into today’s units. Filter by what is being measured to see only length, area, volume, mass, count or time.

Enter your salary before tax and where you live to see the Income Tax, National Insurance and student loan repayments taken each month, and what you take home.

Enter the amount, the rate and the term, and the monthly payment and full schedule are shown.

Enter a starting amount, a return and a horizon, and see how the money grows year by year.

Enter an amount and two years, and see what the amount comes to.

Enter the amount and choose the base month and the review month, and the amount is uprated by the index as in an index-linking clause.

Work out VAT in both directions: add it to a net price, or take it out of a gross price.

Enter the bill, the tip you want to leave and how many you are, and the amount per person is shown.

Choose an appliance or enter its power and running time, add your unit rate, and the energy used and its cost are shown.

Enter the distance, how economical the car is and the price, and the cost of the journey is shown in total and per person.

Daily reference rates from the European Central Bank. Change the amount or currency and the result updates instantly.

Pick two currencies and a period, and the rate is plotted from European Central Bank reference rates.

Enter two dates and the difference is worked out three ways: in days, in weeks, and in calendar parts.

Pick a start date and how far forward or back to count, and the date you land on is shown.

Enter the date of birth, and the age is worked out for whatever day you choose.

Choose what you are counting from and enter the date to see the estimated due date and how far along the pregnancy is.

Look up the week for a date, or go the other way and see which dates a week covers.

Count working days between two dates, with weekends and public holidays removed. Pick a country, since the holidays differ.

Pick a country and a year to see every public holiday with its date and weekday, the bridge days and how many working days the year has.

Choose a year, a country and how many days of leave you would take, and see where the longest breaks are.

Pick two places and a time, and see what the clock says in the other one.

Pick a place and a date to see sunrise, sunset, the length of the day and the three stages of twilight.

Pick a place and a year to see the day length plotted across the year, with the solstices and equinoxes marked.

Pick a holiday or your own date, and the time counts down second by second.

Pick a time, press Start and get a signal when it runs out.

Press Start, and take lap times while the clock runs.

Type the word as it looks in the grid, with ? where you do not know the letter.

Type your letters to see every word that can be made from them.

Type a word to see every word made of exactly the same letters.

Type a word, and the words that end the same way appear, closest rhymes first.

Paste or type your text, and everything recounts as you go.

Type your text and it appears in every format at once. Click Copy for the one you need.

Paste a list with one item per line, and it is reordered according to your choices.

Paste a text and the readability index is worked out, along with the figures behind it.

Type or paste text and it is encoded or decoded as you go.

Encode text that has to go into a web address, or turn an encoded address back into readable text.

Paste JSON and it is reformatted, or squeezed onto a single line.

Enter a value and choose the unit to see the same size in every CSS unit, ready to copy.

Enter a text and the hashes are calculated with four algorithms at once.

Generate random version 4 identifiers, in whichever form you need.

Choose the length and which characters to include, and the passwords are made in your browser.

Enter a timestamp and the moment appears, or enter a date and the number appears.

Enter the content and the code appears. Download it as SVG or PNG.

Paste the original and the changed version to have every difference highlighted, down to individual words.

Enter a pattern and some text to test it on, and every match is highlighted as you type.

Paste a token to see what it contains and when it expires. If you have the key, you can check the signature too.

The tool works both ways: enter a schedule in crontab format to have it explained, or describe the schedule in words to get the expression.

Enter the colour in whichever notation you have, and the others fill in. All three fields stay in step.

Pick a text colour and a background, and the contrast ratio is measured against the WCAG requirements.

This is the IP address websites see when you browse, with what can be read about your connection.

Everything your browser reveals about itself, your screen and your settings, gathered in one place and easy to copy.

Enter an address with a prefix, such as 192.168.1.10/24, to see the network it belongs to and everything that can be worked out about it.

Enter a domain, a web address, an email address or an IP address to see what DNS says about it.

The test tries IPv4 and IPv6 separately and shows which one your browser uses when it can choose.