Turbo C / Turbo C++ Online Compiler

Write and run your Turbo C or Turbo C++ style programs in the browser, with nothing to install. Press Run and the program is compiled with a modern GCC compiler.

Please note: this is not the original Turbo C. Turbo C and Turbo C++ were Borland compilers for DOS from the 1990s. This page runs standard C on GCC, so a few old Turbo C features need a small change before a program will build. The table below shows each one.

Turbo C code that needs changing on GCC

Turbo C code	What happens on GCC	What to do
`#include <conio.h>`	Build fails: the header does not exist.	Delete the line and remove anything that needs it.
`clrscr()`	Not available.	Delete the call. The output panel starts empty on every run.
`getch()` / `getche()`	Not available.	Delete a final `getch()` that only keeps the window open. To read a character, use `getchar()` (supply the character in Stdin before Run).
`void main()`	Builds with a warning.	Write `int main(void)` and end with `return 0;`.
`gets(str)`	Removed from the C11 standard.	Use `fgets(str, sizeof str, stdin)`.
`gotoxy()`, `textcolor()`, `cprintf()`	Not available.	Print with `printf()` instead. There is no standard C version of these.
`graphics.h`, `initgraph()`	Not available.	BGI graphics does not exist on GCC. Rewrite the output as text.
`int` is 16 bits	`int` is 32 bits (4 bytes).	Use a type large enough for the values. Signed integer overflow is undefined behavior in standard C.
`#include <iostream.h>` (Turbo C++)	Build fails.	Use `#include <iostream>` and `using namespace std;`, and run it on the C++ compiler.

Example: a Turbo C program, fixed for GCC

Before (Turbo C):

#include <stdio.h>
#include <conio.h>

void main() {
    int a, b;
    clrscr();
    printf("Enter two numbers: ");
    scanf("%d %d", &a, &b);
    printf("Sum = %d", a + b);
    getch();
}

After (runs on GCC):

#include <stdio.h>

int main(void) {
    int a, b;
    printf("Enter two numbers: ");
    scanf("%d %d", &a, &b);
    printf("Sum = %d\n", a + b);
    return 0;
}

Learn more

Read Turbo C vs Modern C for the full history. For error messages, see the implicit declaration guide. To practise, try the C program examples and C exercises, or open the full C IDE.

Turbo C online compiler FAQ

Is this the real Turbo C?

No. It is a modern GCC compiler running in your browser. Turbo C was a DOS program, and this page does not emulate DOS.

Why does conio.h give an error?

conio.h is a Borland header that GCC does not include. Remove the include, and remove calls such as clrscr() and getch() that came from it.

What can I use instead of getch()?

Usually nothing. Programs add getch() at the end to keep the DOS window open, and the output stays visible here. To read a character, use getchar().

Can I use graphics.h here?

No. The BGI graphics library is not part of GCC, so graphics programs must be rewritten to print text.

Why does my program give a different result than in Turbo C?

In Turbo C an int is 16 bits, and on GCC it is 32 bits. Use a type large enough for the values. Signed integer overflow is undefined behavior in standard C.

Do I need DOSBox?

No. Standard C programs run directly in your browser here.