The All Ordinaries Index (ASX: XAO) is up a respectable 1.5% since 18 December, but one ASX tech stock has left those gains well behind.
The fast-rising stock in question is Calix Ltd (ASX: CXL).
If you're not familiar with Calix, the company earns its keep by creating businesses that solve global challenges in industrial decarbonisation and sustainability.
And despite today's sizeable retrace, Calix shares have been on an absolute tear since mid-December.
Here's what I mean.
Calix shares are currently down a sharp 10.4% today, trading for $1.335 apiece.
That will obviously come as unwelcome news to investors buying the ASX tech share on Monday.
But turn the clock back to 18 December, and you could have picked up Calix shares at an intraday low of just 51.2 cents each.
That's a gain of 160.7%, despite today's pullback.
Or enough to turn an $8,000 investment into $20,859. In less than three weeks!
Why is the Calix share price tumbling today?
With no fresh troubling news out from Calix to explain today's sharp sell-down, it looks like we're seeing some healthy profit-taking today.
After all, over the past five trading days, the ASX tech stock has posted consecutive gains of 9.6%, 10.0%, 11.4%, 15.3%, finishing with a whopping 31.9% gain yesterday.
So, it's only natural that investors may be taking some money off the table here on the third trading day of 2026.
What's been sending the ASX tech stock soaring?
On Friday, Calix responded to a 'speeding ticket' from the ASX, questioning its rapid share price gains and increased trading volume.
The ASX queried, "Is CXL aware of any inf ormation concerning it that has not been announced to the market which, if known by some in the market, could explain the recent trading in its securities?"
To which the ASX tech stock answered, "No."
Looking back at the charts, Calix shares really began their lift off on 19 December, closing up 26.9% on the day.
That big move came after the company announced a three-year contract with an unnamed United States-based customer, reported to be among the world's largest agriculture companies.
The contract involves supplying magnesium hydroxide water treatment products. And management expects it will generate up to $10 million a year in product and services revenue.
Investors reacted positively, with the ASX tech stock noting that it expects to generate the initial revenue from that contract in the first quarter of 2026.
The post Up 161% in 3 weeks, why is this surging ASX tech stock tumbling today? appeared first on The Motley Fool Australia.
Motley Fool contributor Bernd Struben has no position in any of the stocks mentioned. The Motley Fool Australia's parent company Motley Fool Holdings Inc. has no position in any of the stocks mentioned. The Motley Fool Australia has no position in any of the stocks mentioned. The Motley Fool has a disclosure policy. This article contains general investment advice only (under AFSL 400691). Authorised by Scott Phillips.
The Motley Fool's purpose is to help the world invest, better. Click here now for your free subscription to Take Stock, The Motley Fool's free investing newsletter. Packed with stock ideas and investing advice, it is essential reading for anyone looking to build and grow their wealth in the years ahead. This article contains general investment advice only (under AFSL 400691). Authorised by Bruce Jackson. 2026