Pine Script code checker and fixer: find and fix script errors online

Check Pine Script code online for free: SuperCharting's Script Editor finds errors with line numbers, and Auto-fix repairs common mistakes for you.

A Pine Script code checker tells you whether a script will compile and run, and where it breaks if it will not. SuperCharting's Script Editor does this in the browser: it checks your code as you type, points to the line of each error, and has an Auto-fix button that repairs common mistakes and lists every change it made. It is free for now and needs no install. Pine Script is TradingView's language; SuperCharting runs scripts written in the same version 6 syntax in its own engine, and the Pine compatibility page lists which features are supported.

How to check a Pine Script for errors

Open a chart, then open the Script Editor with Ctrl + E or the Script Editor button in the right-hand bar.
Paste your script into the code area, replacing the starter template.
About 600 milliseconds after you stop typing, the console shows the result:

✓ My script (indicator) when it compiles;
✗ line 6: unexpected 'EOF' (or a similar message) when it does not. A red dot appears on the console button, and the console opens on its own.

Click Add to chart. Some mistakes show only when the script runs on real bars, such as a misspelt function name. Those appear as a line that starts with Runtime:, again with the line number, for example Runtime: line 3, bar 0: unknown function ta.foo().

So there are two checks: the compile check while you type, and the run check when the script goes on the chart. A script that passes both is ready to use.

What Auto-fix repairs

When the console shows an error, press Auto-fix, the button right after Save in the editor header. The console shows "Auto-fix: reading your script…". It then puts the fixed version in the editor and lists each change in plain words, for example "Line 3: tab indent replaced with 4 spaces." The last line tells you where the script stands: ✓ The script compiles and runs, or ✗ Still wrong with the line that still has a problem. If you do not like the result, choose Undo Auto-fix in the More menu to get your original back.

The built-in fixer, on every account, handles two kinds of problem:

Old-version code. For a script with no //@version line or a version below 6, it:
sets //@version=6;
turns study() into indicator(), and adds indicator() if it is missing;
adds the missing namespace to old functions (sma becomes ta.sma, max becomes math.max, tostring becomes str.tostring, security becomes request.security);
rewrites iff(c, a, b) as c ? a : b;
changes input(x, type=input.integer) to input.int(x);
changes bare colour names to color.red and friends, and transp=N to color.new(c, N);
replaces x == na with na(x);
changes = to := when a variable declared earlier is given a new value.
Characters that broke the script. Curly quotes, a tab indent or a semicolon at the end of a line become plain quotes, 4 spaces or nothing. It does this only when that character is what broke the script.
The error the checker reports. It repairs an unclosed string or bracket, a stray character, and a misspelt function, variable or colour name (it picks the closest known name). Then it checks again, and repeats until the script runs or nothing more can be fixed.

Auto-fix never edits text inside strings or comments, except the quote characters themselves. If a change would leave the script worse than before, that change is dropped. Every account can run Auto-fix up to 40 times an hour.

The deeper AI check

For accounts the site owner enables, Auto-fix also runs an AI pass after the built-in one. It can fix what simple rules cannot, such as a missing comma between arguments or a block indented wrongly. The console then says "Auto-fix (full AI check)". The AI result is checked again in the same way, and it is kept only if it is no worse than the built-in fixer's. Like any AI it can be wrong, so read the list of changes before you rely on the script.

Common Pine Script errors and what they mean

Console message	Usual cause	Fix
`unexpected 'EOF'`	A bracket or string was opened and never closed	Close it. Auto-fix does this for you
`unknown function ta.foo()` (Runtime)	A misspelt or non-existent function	Correct the name. Auto-fix picks the closest real one
An error on `study(`	Code from Pine version 4 or older	Auto-fix converts it to `indicator(` and version 6
An error on `sma(` or `rsi(` without `ta.`	Version 4 functions had no namespace	Auto-fix adds `ta.` or `math.`
A variable cannot be reassigned	`=` used where `:=` is needed	Auto-fix changes it when the variable was declared before

After the check passes

Save with Ctrl + S. Scripts are saved to your account, up to 500 of them.
Turn an indicator into a strategy and test it in the Strategy Tester. The backtest Pine Script online guide walks through it.
If you are new to the language, Pine Script v6 basics and write your first indicator explain the syntax with examples that run.

What the checker does not do

It does not promise that every Pine Script feature runs. Some built-ins are not supported yet, and the console names them. For example, request.security works on higher timeframes of the chart's own symbol, but not on a different symbol.
It checks that the code runs, not whether a strategy is any good. A script that compiles can still lose money, and nothing here is investment advice.

TradingView and Pine Script are trademarks of TradingView, Inc. SuperCharting is independent and not affiliated with it.