Every cell starting with = is evaluated as a Ruby expression.
Plain text and numbers are stored as-is.
Arithmetic
Standard Ruby operators work in formulas:
| Operator |
Example |
Result |
+ - * / |
=2 + 3 * 4 |
14 |
** |
=(10 - 2) ** 3 |
512 |
% |
=100 % 7 |
2 |
Cell References
Reference cells by column letter + row number:
=A1 * 4
=A1 + B1
References cascade: if B1 depends on A1, changing A1 updates B1 automatically.
Cell Ranges
Use Ruby’s .. range syntax to work with multiple cells.
The result is a full Enumerable:
=(A1..A10).sum(&:to_f)
=(A1..A10).count { |v| v > 50 }
=(A1..A10).max_by(&:to_f)
=(A1..A10).min_by(&:to_f)
=(A1..A10).sort_by(&:to_f).first(3)
=(A1..A10).select { |v| v > 0 }
=(A1..A10).map { |v| v * 2 }
Column Ranges
Use A:A syntax to reference an entire column (all rows):
=(A:A).sum(&:to_f)
=(B:B).count { |v| v > 0 }
=(A:A).max_by(&:to_f)
Multi-column ranges work too: A:C covers all cells in columns A, B, and C.
String Methods
Call any Ruby string method on cell values:
| Method |
Example |
Description |
.upcase |
=A1.upcase |
Uppercase |
.downcase |
=A1.downcase |
Lowercase |
.capitalize |
=A1.capitalize |
Capitalize first letter |
.reverse |
=A1.reverse |
Reverse string |
.length |
=A1.length |
Character count |
.gsub(a, b) |
=A1.gsub("a", "@") |
Replace characters |
.split(sep) |
=A1.split(",") |
Split into array |
.strip |
=A1.strip |
Remove whitespace |
.include?(s) |
=A1.include?("text") |
Check if contains |
.start_with?(s) |
=A1.start_with?("http") |
Check prefix |
Helper Functions
Math
| Function |
Description |
Example |
sum(...) |
Sum of values |
=sum(1, 2, 3) |
avg(...) |
Average |
=avg(10, 20, 30) |
min(...) |
Minimum |
=min(5, 2, 8) |
max(...) |
Maximum |
=max(5, 2, 8) |
round(n, digits) |
Round to digits |
=round(3.14159, 2) |
sqrt(n) |
Square root |
=sqrt(144) |
abs(n) |
Absolute value |
=abs(-42) |
ceil(n) |
Round up |
=ceil(3.2) |
floor(n) |
Round down |
=floor(3.8) |
pow(base, exp) |
Exponentiation |
=pow(2, 10) |
pi |
Pi constant |
=round(pi, 4) |
All math helpers accept cell references: =sum(A1, A2, A3).
Text
| Function |
Description |
Example |
concat(...) |
Join values as text |
=concat(A1, " ", B1) |
md5(text) |
MD5 hex digest |
=md5("hello") |
Images
Call .to_image on any URL string to display it as an image in the cell:
="https://example.com/photo.jpg".to_image
Combine with md5 for gravatar avatars:
=("https://s.gravatar.com/avatar/" + md5(A1) + "?s=80").to_image
Only HTTP and HTTPS URLs are accepted.
HTTP
| Function |
Description |
Example |
fetch_json(url) |
Fetch and parse JSON |
=fetch_json("https://api.example.com/data")["key"] |
fetch_text(url) |
Fetch raw text |
=fetch_text("https://example.com/file.txt") |
JSON responses support [], dig, keys, values, and size.
Requests are cached for 5 minutes. Private networks and localhost are blocked.
Date & Time
Date and Time are available in formulas via safe wrappers.
Shorthand helpers today and now are also available.
=today.to_s # "2025-06-15"
=now.strftime("%H:%M") # "14:30"
=today.strftime("%A") # "Sunday"
=Date.parse("2025-12-31").to_s # "2025-12-31"
=Date.civil(2025, 6, 15).to_s # "2025-06-15"
=(Date.parse("2025-12-31") - today).to_i # days until
=today.year # 2025
=today.month # 6
=today.monday? # true/false
=(Date.parse(A1) - Date.parse(B1)).to_i # days between two cells
Date arithmetic works naturally: Date.today + 30 returns a date 30 days
from now. Date ranges are iterable: (date1..date2).count.
Custom Functions
Define reusable Ruby methods in the Custom Functions panel (f(x) button).
Functions are available in any cell formula:
# In the panel:
def tax(amount)
amount * 0.077
end
def grade(score)
case score
when 90.. then "A"
when 80..89 then "B"
when 70..79 then "C"
else "F"
end
end
# In any cell:
=tax(A1)
=grade(D5)
=tax(discount(B2, 15))
Functions can call other custom functions, use cell references, and access
all built-in helpers. Press Cmd+S in the editor to save.
Conditionals
Use Ruby’s ternary operator or case/when:
=A1 > 100 ? "high" : "low"
=A1.to_i.even? ? "even" : "odd"
Rules are managed in the Style & Format panel. Each rule targets a cell or range
and can define a style expression, a format expression, or both.
Style Expressions
Return a CSS class name to style the cell:
value > 100 ? "danger" : value > 50 ? "warning" : "success"
Available styles: danger, warning, success, info, highlight, muted, bold, italic.
Transform how the cell value is displayed without changing the underlying data:
"#{value} CHF" # append currency
value.to_i > 0 ? "ON" : "OFF" # boolean display
"#{value}%" # percentage
value > 1000 ? "#{value / 1000.0}k" : value.to_s # compact numbers
The expression receives value (the cell’s computed value) and can reference
other cells and custom functions. The original value is preserved — only the
display changes.
Keyboard Shortcuts
| Key |
Action |
| Arrow keys |
Navigate cells |
| Shift + Arrow |
Extend selection |
| Enter |
Edit cell / Confirm |
| Escape |
Cancel / Clear selection |
| Tab / Shift+Tab |
Move right / left |
| Delete |
Clear cell |
| Ctrl+C |
Copy |
| Ctrl+X |
Cut |
| Ctrl+V |
Paste |
| F1 |
Show this help |
