CryptonicTools

How to track a crypto portfolio in your browser

Open tool

Use the local portfolio tracker: add holdings, store them in localStorage, mark to CoinGecko USD, and read cost basis P&L without an account.

Open the tool

Track what you hold and whether you are up or down versus your cost basis — privately in the browser, without uploading balances to CryptonicTools.

Launch Portfolio Tracker

Purpose

Track what you hold and whether you are up or down versus your cost basis — privately in the browser, without uploading balances to CryptonicTools.

When to use it

  • You want a quick multi-asset P&L without connecting a wallet
  • You keep a personal cost basis per coin and need live marks
  • You prefer localStorage over exchange portfolio UIs
  • You are teaching someone portfolio basics without KYC apps

How to use it

  1. Add a holding. Enter the coin, amount, and your average entry price.
  2. Save locally. Holdings persist in localStorage on this browser profile only.
  3. Review live value and P&L. Live USD marks come from CoinGecko; P&L is value minus cost basis.
  4. Update when you trade. Edit amounts and entries after buys or sells so the book stays honest.

Benefits

  • No account and no custodial sync
  • Cost-basis P&L that matches how many investors think
  • Fast mobile checks on a phone browser
  • Works alongside converter and DCA tools on the same site

Pitfalls to avoid

  • Clearing site data deletes the portfolio
  • No cross-device sync by design
  • Does not include DeFi wallet positions unless you enter them manually
  • Spot USD marks ignore local tax lots and wash-sale rules

Where your data lives

Everything stays in your browser’s localStorage. That is a feature for privacy and a responsibility for backups: export screenshots or notes if the book matters. CryptonicTools servers never receive your holdings list.

Shared computers are a poor fit unless you clear data after. Treat the tracker like a local notepad with live prices, not a bank.

How P&L is calculated

Cost basis is amount × your entry price per line. Live value uses CoinGecko USD. P&L equals value minus cost basis. That is unrealized P&L for spots you still hold; it is not a tax lot engine.

For rough tax sketches, pair with the capital gains helper and keep proper records elsewhere. This is not tax or financial advice.

Benefits of a no-login book

Many portfolio apps want wallet connect or exchange API keys. This tracker skips that surface area. You gain speed and privacy; you lose automatic on-chain discovery. Enter LP tokens or staked amounts manually if you want them in the total.

Related links

Updated 2026-09-09. Educational only — not financial advice.

Frequently asked questions

Where is my portfolio stored?+

Only in your browser’s localStorage. Clearing site data deletes holdings. Nothing is uploaded to CryptonicTools servers.

How is P&L calculated?+

Cost basis is amount × your entry price per coin. Live value uses CoinGecko USD prices. P&L equals value minus cost basis.

Can I sync across devices?+

Not yet. Tracking is local-only by design (no account). Export or screenshot balances if you need a backup.

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