Bitcoin DCA calculator comparison: 17 tools, 8 real answers

Of 17 Bitcoin DCA calculators tested on 26 August 2026, only 8 let you set both a start and an end date. Given identical inputs those 8 return answers ranging $29,344 to $31,248. bennet.org scored highest at 20 of 24. This site scored 19 and finished second.

Jon Phillips · 26 August 2026 · 12 min read

I run one of these tools, so start with that: this article ranks 17 Bitcoin DCA calculators and mine is one of them. It came second, not first.

The rubric below was written and frozen in version control at commit 8402486 before a single tool was opened. That ordering is the only thing standing between this and a rigged comparison, because a reviewer who writes the rules after seeing the results produces something that looks identical from the outside.

And you cannot currently verify that. The repository is private, so the commit ordering is my word, not your check — which is an uncomfortable thing to admit in an article whose main complaint is that most of these 17 tools will not tell you where their numbers come from. So: the whole rubric is published as its own page rather than summarised, every score carries a quote you can go and test against the live tool yourself, and the one claim you have to take on trust is the timestamp. If that is not enough for you, the scorecard is complete enough to re-derive without me.

Every claim below was checked on 26 August 2026. Where I could not check something, I say so rather than leaving it out.

The finding is not the ranking

I set out to run one ordinary question through every calculator I could find:

$50 a week into Bitcoin, from 1 January 2018 to 1 January 2021.

eight of 17 can express it. The rest cannot close a window: they offer "3 years ago" or "8 years ago" from a dropdown, or a start date with no end date, so every answer runs to today and changes tomorrow. That is not a small limitation. A window you cannot close is a window you cannot cite, because the number moves underneath the citation.

eight of them produced an answer for this plan. That is not quite the same eight — dcaBTC has no end-date control but reaches 1 January 2021 through a three-year duration preset, and CryptoDCA.io can close a window but was not run. Here is what they said.

Look at the money paid in first, because that is not an answer — it is the question. five calculators agree the plan costs $7,850 across 157 purchases. AlphaSquared makes 163 and spends $300 more of your money than you asked it to. And bitcoincalculator.tools makes 149 — it asks for a total rather than an amount per purchase, so it quietly hands you $53 a week instead of the $50 you wanted.

The window is 156.6 weeks long. four different answers to "how many purchases is that": 149, 157, 161, 163. None of them is wrong exactly, and not one tool states which convention it uses.

That one is a changed plan, not a different answer, so it does not belong in the disagreement. Measured per dollar actually paid in, AlphaSquared and this site are 0.23% apart: its bigger headline number is mostly just the extra $300. Quoting the full $29,344–$35,784 range as "how much these tools disagree" would inflate the finding with a plan change, which is the sort of thing this article exists to complain about.

The real disagreement is among the five tools running an identical schedule. There, the same $7,850 becomes anything from $29,344 to $31,248 — a spread of $1,904, or 6.5%, on money that was paid in on the same dates.

Nobody here is doing bad arithmetic. They are using different price sources, and they are valuing your Bitcoin on different dates. dcaBTC is the low outlier at $29,344: its 1.0564 BTC at that value implies about $27,777 per bitcoin, while the other four imply $29,354 to $29,389. The first of January 2018 was a Monday, so 157 weekly purchases end on 28 December 2020 — when Bitcoin was near $27,000. That is consistent with dcaBTC valuing your stack on the day of your last purchase while everyone else values it at the end of your window. Consistent with, not proven, because dcaBTC publishes no methodology at all.

Which is the whole problem. Every one of these tools is defensible. You cannot tell which convention you are getting, and the choice is worth thousands of dollars.

The rubric, before the results

Eight axes, twenty-four points. They are written from the reader's question — which of these should I use, and can I trust the number it gives me? — and deliberately not from a feature list of my own product. Two of them are places I already knew this site does badly. That was the point: a rubric its author sweeps is a rubric its author designed backwards.

The equal weighting is a choice, and it is mine. Every axis is worth three points, which quietly decides a lot. If you care most about getting an answer without an account and being able to send someone the link, weight access and permanence heavily and this site drops several places. The full grid is published below precisely so you can do that arithmetic against me rather than take the total on faith, and the rubric has its own page with the anchors in full.

The scorecard

The winner is bennet.org, at 20 of 24. It is a personal site, written by one named person, and it beats every commercial tool in the field including mine.

It earns it. It names its price feeds — the CoinDesk composite index, recent closes from Kraken, the European Central Bank for currency conversion. It states its execution assumption ("contributions are assumed to execute at the period close") and its exclusions ("fees are ignored by default"). It puts your inputs in the URL so you can send someone the exact run. And it says, in plain words on the page: "Independent, no sponsored content or affiliate links."

It loses exactly one axis: it does Bitcoin and nothing else. That gap is the reason this site exists, and it is not enough to make me the better tool for most questions.

The median score is 13 of 24. The bottom of the table is worth as much attention as the top.

Three numbers that describe the whole category

five of 17 name their price source. Not "market data" or an exchange logo — an actual feed a reader could go and check. The other twelve show you a number to the cent and will not tell you where it came from.

two of 17 do not backtest at all. Bitcoin Well's tool is titled "Bitcoin DCA Calculator" and its own disclaimer describes "a simplified 4-year cycle model based on historical halving patterns… a speculative theory." MyDCACalc is stranger: its page is titled "DCA Backtest Calculator" and promises "actual historical price data… across real market cycles including crashes, recoveries, and bull runs," then discloses two paragraphs later that returns "use historical annual averages… compounded annually and applied uniformly across the period." A uniformly compounded average cannot contain a crash. Both sentences are on the same screen.

two of 17 have a commercial interest in the answer and do not disclose it. Which brings us to the most useful thing I found.

The same behaviour, three different levels of telling you

Taking money from an exchange does not make a calculator dishonest. Hiding it does. Four tools here take exchange money and differ only in whether — and where — they mention it:

• bennet.org states it on the tool page itself: "Independent, no sponsored content or affiliate links." No referral, no ads, no paid tier.
• bitcoincalculator.tools runs five affiliate placements — MEXC, RedotPay, Coinbase, TradingView and a CFD broker, with utm_medium=affiliate right in the URL and several tagged utm_content=post-result, meaning beside your number. It also carries the most complete disclosure of anyone: the placements are labelled SPONSORED, there is an affiliate disclosure and a financial disclaimer, and there is a "Hide affiliate recommendations" control. Heavy monetisation, openly labelled.
• Bitbo discloses more than almost anyone — "Bitbo receives compensation with respect to its referrals for out-bound crypto exchanges and crypto wallet websites", and even that "Wallabit Media LLC and/or its owner/writers own Bitcoin." That second sentence is rare and creditable. It is simply on a different site from the number.
• CryptoDCACalculator is the most transparent tool here about its data — the only one to name its feed, its history and its cadence, and to quantify the fees it excludes — while running four links to binance.com/register?ref=392703655. The words affiliate, commission, referral and sponsored appear nowhere on the page.

A referral code is not a scandal. An undisclosed one, on a page whose entire purpose is to tell you what Bitcoin would have done, is a different thing.

The exchanges score worst, and not for the reason you would guess

Two of the 17 are run by companies that will sell you the Bitcoin: Kraken (24 available, scored 9) and Uphold (15). They are the bottom and the middle of the table, and the independence axis is barely why — both score 1 there, the same as Bitbo, because an exchange selling Bitcoin is the least surprising commercial interest in the world and nobody could miss it.

They lose on the boring things. Kraken's "Since" control is a list of years — 2021, 2022, 2024, 2025, 2026 — with no end date, so you cannot ask it about any specific month, and it never tells you how much Bitcoin you would have. Uphold does better than every other exchange tool and closes a window properly, then reads its own URL a month early: ?dateStart=2018-01&dateEnd=2021-01 renders as "December 2017 to December 2020".

The thing that would make an exchange calculator untrustworthy — a thumb on the scale — is not what went wrong. What went wrong is that nobody checked them.

Three tools print a number that is not what its label says

This is the category's real failure, and it has nothing to do with money.

Spark offers "Last 3 Years" and "Last 5 Years" buttons its data cannot serve. Both return "Unable to fetch historical Bitcoin prices" — and when they fail, the previous result stays on screen. Click "Last 5 Years" after a successful one-year run and you are looking at an error message above a panel still showing the one-year answer. Its byline reads "Invalid Date".

bitcoincalculator.tools heads its result "PORTFOLIO VALUE TODAY" and shows $30,910 for a window ending in January 2021 — a figure that implies $29,388 a bitcoin, which was the price then, not now. The number is right; the word today is wrong. The same panel reported "FREQUENCY: Monthly" while the control I had set read Weekly, twice, from a cold page load.

dcaBTC shows $NaN.

None of these is a rounding dispute. They are labels that do not describe the number underneath them, on pages whose only job is to put a number in front of you.

Where this site loses

I scored 19 of 24, second. Both lost axes are real and neither is a technicality.

You cannot link to a run. Every plan you build here lives in your browser and nowhere else. There is no shareable URL and no export. Four other calculators can hand you a link that reproduces the exact result; one of them writes it as a readable path you could almost type from memory. This is a genuine deficiency and it is on the list to fix.

A cold visitor gets one asset. Of 71 things you can compare here, Bitcoin is the only one available without an account. Ethereum, Solana, gold, the S&P 500 and the Nasdaq 100 need a free sign-up; the other 65 need a paid plan. Comparing Bitcoin against something else is the entire premise of this site — the about page says so in as many words — so by my own rubric, the useful part is behind a sign-up, and that scores a 1.

What this site does have is the thing the category mostly lacks, and it would be absurd to spend an article demanding that others name their price feed without naming mine. Bitcoin comes from Yahoo Finance daily closes back to 17 September 2014. The S&P 500 is ^SP500TR, the Dow is DIA and the Nasdaq 100 is QQQ — total-return series, not the price indices, because a price index understates a real holding by every dividend it ever paid. Housing is FRED, series USSTHPI and the fifty state equivalents. Inflation is CPI-U. Gold, silver and oil are continuous futures — GC=F, SI=F, CL=F. The whole set refreshes nightly, and the knowledge base carries the start date and the exclusions for every one of them.

My figure above — 1.05667490 BTC and $31,038.93 — comes from those closes and that schedule. Fees, spreads and taxes are excluded, exactly as they are in every other tool here.

That is worth precisely as much as you think it is, given that I am the one telling you.

What this does not prove

• It is one rubric. Eight axes chosen by me, weighted equally by me. A reader who cares only about "does it work on my phone and is it free" would rank this field almost in reverse. The axes are published so you can disagree with them specifically rather than generally.
• It is one day. Everything was checked on 26 August 2026. dcaBTC's data has been stalled since May 2025, so that one is unlikely to change soon; the rest could be different next week.
• One tool was reached differently. Bitbo blocks automated browsers, so it was checked by hand in an ordinary browser session while the others were driven the same way. It could not be included in the phone check at all.
• Four tools were added late. bitcoincalculator.tools, Kraken, Uphold and Spark were scored after the first pass, once a real search result showed they rank on page one and my first sweep had missed them. They were scored against the same anchors, but they were not in the phone sweep.
• One entrant is also a source. Spark is scored here as a tool, and its separate comparison article was one of the documents used to pressure-test this piece before publication. Those are different jobs, but you should know they overlap.
• Scores are capability, not one identical run. Because most tools cannot express the standard question, each was scored on what it can do rather than on a single shared result. Saying these were all "tested against the same question" would be false, and that most of them cannot answer one ordinary question is the finding, not a flaw in the method.
• I am not neutral. I built one of the entrants. The rubric predates the scoring in a public commit history, which is a check you can perform rather than a promise you have to accept.

If you only take one thing

Before you trust any number a DCA calculator gives you, find out three things: where it got the price, how many purchases it thinks fit in your date range, and what day it valued your holdings on. Twelve of the 17 tools here will not tell you the first. Not one will tell you the second. And the difference between the answers is $1,904 on a $7,850 plan.

If you want to run the comparison this site is built for — the same schedule against something other than Bitcoin — the simulator is here, and what a decade of it actually returned and how long buyers spent underwater are the two measurements I would read first.