Mashmatrix Sheet
An Excel-shaped grid of books and sheets that runs inside your org, from an eighteen-year-old Tokyo company that has shipped three major releases a year since at least 2020.
What it does well
- The most capable editor in the landscape. Paste straight from Excel with lookups resolved, tiling and discontiguous multi-range paste, Ctrl+Z undo with Ctrl+Shift+Z redo, and a right-click revert for just the selected cells or ranges.
- Upsert without Data Loader. A dedicated mode that matches pasted rows on a Salesforce ID, an External ID or another unique field, updates the matches and inserts the rest.
- A shipped developer surface. The grid as a Lightning Web Component on pages, in Screen Flows, in the Utility Bar and inside your own components, with a documented JavaScript API, Message Channel and Platform Event APIs, and a separate Agentforce agent extension.
- A steady release rhythm. Major releases every April, August and December since at least 2020; release 38.0, on 23 August 2026, added Union Sheets that merge up to three objects into one set of rows.
What it is
Mashmatrix Sheet is a managed package from Mashmatrix, Inc., a Tokyo company founded in January 2008, listed on the AppExchange since 6 September 2016. It is shaped like Excel on purpose: a book is a workbook of sheets, and each sheet is a list over one Salesforce object.
Several objects meet on one screen in three ways. Related sheets in a split screen show parent, child and grandchild records that move together as you select a row. Custom related sheets link objects that have no relationship in your data model by matching field values. And since August 2026 a Union Sheet merges two or three objects into a single set of rows with shared columns.
How it is built
The grid reaches Lightning pages as a Lightning Web Component, the Sheet component, on record, home and app pages, in Screen Flows, in the Utility Bar and inside your own components. The full application is a Visualforce-hosted page, which is also how it is placed on an Experience Cloud site. Queries and saves run in your org: a sheet fetches its rows from Salesforce and pages them in the browser, and saves go back in batches whose size an admin sets, from 1 to 10,000 records. No callouts or vendor services appear in its documentation.
Your configuration is records in the package’s sixteen custom objects, inside your org: books, sheets, views, columns, formats, action buttons and formulas, with no documented export or configuration API. In-sheet data columns hold values that have no Salesforce field behind them, so that data lives in Mashmatrix’s objects too. On top of Salesforce’s own security sits a second layer of its own: custom permissions prefixed MsmxPerm_, per-operation record limits, and folder sharing to roles and public groups at four access levels.
What it publishes about its limits
Mashmatrix publishes its constraints, including dedicated limitations pages for its two most complex features. The fetch maximum is 20,000 rows. Summary rows cover only the records fetched, and say so with a warning mark. Lazy rendering switches on automatically at 500 or more records per page. Row grouping is one level; column headers group up to three tiers. Child records open in a linked pane rather than expanding under their parent row.
Copy, paste and direct typing do not work on mobile. Professional Edition needs a separate package. Keyboard shortcuts are documented for copy, paste, undo, redo, delete and direct typing; arrow-key movement, tab order and focus are not, and no accessibility statement was found in its 232 documentation pages, in English and Japanese.
Price
$18 per user per month, list price, for the Standard tier — $216 per user per year. The Enterprise tier is $24 and adds bulk approval, bulk merge and the time-series matrix. A 30-day trial, with no user limit, is available once, on a first contract. Mashmatrix’s Japanese price page sells the base license at ¥1,500 per user per month before tax, with the same three features as separately priced options, and routes contracts of 100 users or more to a quote. The Japanese page also states that contracts are annual, with no refund mid-term, and that monthly payment needs ten or more licenses.
Common complaints
Little criticism is on record, and almost all of the review record is in Japanese. What we read: Its 2 AppExchange reviews, 6 reviews on ITreview and 16 on BOXIL SaaS (two Japanese review sites), read on 7 October 2026.
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Configuring sheets with many fields
An April 2026 reviewer found the fine-grained usability poor when setting up a sheet with many fields, such as moving several columns to a new position at once. Mashmatrix shipped bulk column changes in release 37.0 that month and more column tools in release 38.0 in August 2026. A BOXIL reviewer separately raises how fast operations process.
“the UI's fine-grained usability is poor” — Sales user, ITreview (translated from Japanese), April 2026
Evidence 1 of the 6 ITreview reviews, and one BOXIL review on speed.
ITreview reviews · BOXIL SaaS reviews · Mashmatrix: release 37.0 · Mashmatrix: release 38.0
What reviewers and each vendor’s own documents say, with links; counts are of the reviews we read, not of customers, and quotes are cut short. Nothing was installed or tested. Rowhouse has no reviews yet: it has not shipped.
Choose Mashmatrix Sheet when
- Keyed upsert from Excel is the main job: loading and reconciling data by External ID, not just editing what is already there.
- You need the time-series matrix for forecasts, budget against actual or per-period effort, or bulk merge of up to 100 records, or bulk approval.
- You need the grid inside a Screen Flow, in the Utility Bar, or wired into your own Lightning web component through a documented API.
- You want Japanese-language product, documentation and references from a vendor in Japan.
Rowhouse vs Mashmatrix Sheet Switching from Mashmatrix Sheet
Checked 2026-10-07; due for a re-check by 2027-04-07. These are each vendor’s own published claims; nothing was installed or tested. Something wrong? Tell us and we will correct it.
Mashmatrix Sheet: questions
How much does Mashmatrix Sheet cost?
The AppExchange listing publishes a list price starting at $18 per user per month, read on 6 October 2026, which is Mashmatrix’s Standard tier. Its Enterprise tier, at $24 per user per month, adds bulk approval, bulk merge and the time-series matrix.
Does Mashmatrix Sheet run inside Salesforce?
Yes. Queries and saves run in your org, configuration is stored in the package’s sixteen custom objects there, and Mashmatrix’s user guide says that because everything runs on the Salesforce platform there is no need to worry about data leaking outside.
How many rows can Mashmatrix Sheet load?
A sheet fetches up to its Max Fetch Record Num setting, 2,000 by default and at most 20,000, then pages those rows 200 at a time in the browser. That is a published configuration maximum; Mashmatrix publishes no benchmark.
Why does Mashmatrix Sheet have so few AppExchange reviews?
The listing shows two reviews, both five stars, dated 12 September 2016 and 5 October 2026, and most of its other located reviews are on the Japanese platforms ITreview and BOXIL. Two reviews say nothing, either way, about how widely it is used.
Three things you can verify without asking us
Nobody should pay per seat to edit a thousand rows.
Compare it on your own data: install it beside the grid you have, and keep both until you are sure.