How to use Sumico

Write one calculation per line. The answer appears on the right as you type, and a click on it copies it. Every result on this page is calculated by Sumico in your browser.

Arithmetic
Percentages
Large numbers
Variables, labels and comments
Totals
Units
Currencies
Dates and time
Functions and constants
Number formats
Keyboard shortcuts

Arithmetic

2 + 3 * 414
(2 + 3) * 420
2 ^ 101,024 Power
10 mod 31 Remainder
5!120 Factorial
12 plus 8 times 228 Words work as operators too

Percentages

20% of 45090
5% on 200210 Add a percentage
10% off 8072 Take a percentage off
1200 + 20%1,440
15 as a % of 6025% What share one number is of another
20% of what is 50250 The whole from its part

Large numbers

5k5,000
2.5M2,500,000
3 thousand3,000
1.5 billion1,500,000,000

Variables, labels and comments

price = 450tax = 20%price + tax540 Name a value, then use it below
Rent: 12001,200 Text before a colon is a label
1200 // monthly1,200 Everything after // is a comment
# Budget A line starting with # is a heading

Totals

12080sum200 Adds up the lines above, up to a blank line
1020average15
50prev * 2100 The result of the line above

Units

10 km in miles6.21 miles
5 ft 11 inches in cm180.34 cm
1 hectare in acres2.47 acres
3 l in cups12.68 cups
70 kg in lb154.32 lb
100 km/h in mph62.14 mph
30 °C in °F86 °F
2 GB in MB2,000 MB
2 hours 30 minutes in minutes150 minutes
90 degrees in radians1.57 rad
12 pt in px16 px

Currencies

$100 in EUR€87.13
50 GBP in USD$66.85
100 euro in yen¥18,035.41
$30 + €20$52.95 Mixed currencies convert to the first one
1 BTC in USD$80,341 Crypto too

Dates and time

todaySep 27, 2026
today + 3 weeksOct 18, 2026
next fridayOct 2, 2026
3 days agoSep 24, 2026
in 2 weeksOct 11, 2026
December 25 - today89 days Days until a date
now in TokyoSep 27, 2026, 9:27 pm Time in another city or zone
2:30 pm in London12:30 pm

Functions and constants

sqrt 164
round(3.14159)3
abs(-7)7
log 10003
sin 300.5 Degrees or radians, as set in Preferences
min(3; 7; 1)1
2 pi6.28

Number formats

255 in hex0xff
0xFF255
10 in binary0b1010
1500000 in sci1.5e6

Keyboard shortcuts

`Ctrl`+`N`	New document
`Ctrl`+`P`, `Ctrl`+`K`	Switch documents
`Ctrl`+`Shift`+`D`	Duplicate the document
`Ctrl`+`Shift`+`C`	Copy the result of the current line
`Ctrl`+`Shift`+`0`	Wrap the line in parentheses
`Ctrl`+`Shift`+`Backspace`	Clear the document
`Ctrl`+`F`	Find in the document
`Ctrl`+`=`, `Ctrl`+`-`, `Ctrl`+`0`	Zoom in, out, reset
`Ctrl`+`O`, `Ctrl`+`S`	Import, export a file (desktop app)
`Ctrl`+`,`	Preferences
`F1`	This help

Exchange rates

The app refreshes rates when it is online and keeps working offline with the last rates it has, marking stale ones with a dot. Examples on this page use the rates of 2026-09-20.