Stock Price % Mover (buy price → target %)
Calculator that answers 'what's the price if my stock goes +30%?' or 'where's my -10% stop-loss line?' at a glance. Enter your buy price and currency (¥ / $), and instantly see target prices for +100% / +50% / +30% / +20% / +10% / 0% / -10% / -20% / -30%. Add a custom % row for your own take-profit or stop-loss target. Great for placing limit orders, planning entry/exit, or charting milestones up to a 10-bagger (+900%). Runs entirely in your browser — your numbers are never uploaded.
How to use
1) Pick the currency (¥ JPY or $ USD). 2) Enter your buy price (per share) — target prices for +100% / +50% / +30% / +20% / +10% / 0% / -10% / -20% / -30% and the difference from your buy price are computed instantly. 3) Type a custom % and click Add to track your own take-profit or stop-loss line. There's no run button; the table updates live.
FAQ
- How is the '+30%' price computed?
- buy price × (1 + change% / 100). E.g. with a buy price of 100 and +30%, that's 100 × 1.30 = 130. The diff is (target − buy), so +30 in this case.
- Does the currency toggle apply an FX rate?
- No. The toggle only switches the symbol (¥ / $) and formatting (JPY uses whole numbers, USD uses 2 decimals). No FX conversion — that would require an external API, which conflicts with the site's no-uploads policy.
- How many custom % rows can I add?
- No limit. The only guard is against duplicate values — +25 / +75 / -5 and so on can all coexist. Each custom row has a Remove button.
- What's a 10-bagger in %?
- +900%. A 10× price is the original plus 9× the original. Type 900 into the custom field and click Add to pin the 10-bagger target price in the table.
- Can I include share count or commissions?
- This tool is intentionally focused on per-share price and %. For post-tax P/L or loss carry-over, use the Japanese capital gains tax tool on the same site.
- Is my input uploaded?
- No. Both the buy price and the computed prices stay in your browser and are never sent to any server.
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