I found this online tool for planning a knitted piece. I hope it helps you. Uses:
- If I want to decrease 14 stitches over 6 inches – how many rows should I work between decreases?
- My pattern needs me to increase 13 stitches evenly over a row – how often do I increase?
- I want to knit something 13 inches wide – how many stitches do I cast on?
- I want to knit a piece 22.5 inches long – how many rows do I work?