If you hold more than one crypto asset, you've probably run into this without naming it: you set out to hold, say, 50% Bitcoin and 50% Ethereum. Six months later you check your wallet and it's 70/30, because Bitcoin had a better run. Nothing about your plan changed. The market just moved the numbers for you.

That drift is normal. What you do about it is called rebalancing.

The basic idea

Rebalancing means periodically buying and selling to bring your portfolio back to the percentages you originally chose. If Bitcoin drifted from 50% to 70% of your holdings, rebalancing means selling some Bitcoin and buying more Ethereum until you're back near 50/50.

It sounds almost too simple to have a name. But it's one of the few disciplines in investing that forces you to do the thing that's mechanically correct and emotionally hard: sell some of what just went up, and buy more of what just went down. Nobody feels like doing that in the moment. A rule that does it for you removes the feeling from the decision.

Why crypto drifts faster than almost anything else

Rebalancing isn't a crypto-specific idea. Stock and bond portfolios drift too, just more slowly. Crypto assets can move 10-20% in a single day, which means a portfolio that was on target last week can be meaningfully off target this week. If you're only checking in occasionally, the gap between your intended allocation and your actual allocation can get large before you notice.

That volatility cuts both ways. It's exactly what makes rebalancing valuable (there's more drift to correct, more often) and exactly what makes it easy to skip (checking and manually trading every time something moves 15% isn't realistic for most people).

Three ways people handle this today

Ignore it. Set an allocation once and never touch it again. Simple, but your portfolio's actual risk profile can end up nothing like what you originally intended. A "diversified" portfolio that drifted to 90% in one asset isn't diversified anymore, even if that's not what you meant to happen.

Manual rebalancing. Check in periodically, do the math, place the trades by hand. This works, but it's tedious, easy to put off, and easy to talk yourself out of ("I'll just wait and see if it comes back"). The trades that manual rebalancing asks you to make are also the ones that feel worst in the moment - selling your winner, buying more of your loser.

A predefined index or copied strategy. Some tools solve drift by putting you into a preset basket, or by letting you copy someone else's allocation. That removes the manual work, but it also removes your choice of what to hold and at what weights. You're not rebalancing your portfolio anymore - you're rebalancing someone else's.

What a good rebalancing rule actually needs

A rebalancing strategy needs two decisions per asset: a target percentage, and a tolerance band - how far you'll let that percentage drift before it's worth trading. Too tight a band and you're trading constantly on noise, paying fees for nothing. Too loose and you've effectively turned rebalancing off. Somewhere in the middle is a band that only triggers a trade when the drift is meaningful.

This is also where the "predefined index" shortcut breaks down. Your tolerance for how much a small-cap altcoin should be allowed to drift is not the same as your tolerance for how much Bitcoin should drift. A one-size-fits-all rule can't account for that. A rule you set yourself, per asset, can.

How Rebalance approaches this

Rebalance lets you define exactly which assets to hold and what percentage each should be - any mix, not a predefined index or someone else's basket - along with a tolerance band per asset. When something drifts outside its band, Rebalance shows you exactly what it would trade to bring things back on target. You can preview it and trigger the rebalance yourself with one click, or turn on weekly or monthly automation and let Rebalance check your portfolio and trade on its own, within a trade limit you set. No manual math, no spreadsheet, no talking yourself out of the trade that feels wrong but is mechanically right.

Rebalance also happens to be looking for something else while it's in your portfolio anyway: opportunities to realize tax losses. That's a big enough topic to deserve its own post - read about how Rebalance approaches tax-loss harvesting next.

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