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Hands working on a Calc spreadsheet at a learner's desk

LibreOffice Calc guide

Can your Calc formulas survive a real deadline?

One sheet at a time, the task gets done. This guide explains spreadsheets, formulas, and formatting for everyday work such as budgets, lists, and summaries — sheets other people can read, and that still compute correctly after you edit them.

Start with the first sheet Calc help and extensions

Starting point

A sheet you can finish in one sitting

This LibreOffice Calc guide covers Calc help, cell formats, and practical data tasks you can finish in one sitting. Use it for a monthly budget, a stock list, a summary for a meeting, or a set of records you need to sort and total without breaking the links between rows.

The order matters. Learn how values and rules sit in cells first, then how references move, then how functions, formats, sorting, filters, charts, and print setup hold together. Each part builds on the last, so a sheet you make today still works when someone else edits it next month.

Jump to the part you need

Tell us the task — a budget, a list, a summary — and we will point you to the part of this guide that answers it.

The filed pile

How a Calc sheet holds together

Each sheet below covers one job in the order you meet it at the desk. Read them in sequence the first time; afterwards, jump to the sheet that matches the task in front of you.

Values and references

A spreadsheet is a set of values and rules

Each cell can hold a value, a date, text, or a formula that computes from other cells. Calc displays the result, while the formula bar shows the rule behind it. Keeping values and rules separate makes a sheet easier to audit: click any total and you can see exactly which cells it depends on. A total that is typed by hand cannot be checked in the same way, and when the numbers underneath change, a typed total stays wrong without telling you.

Start a new sheet by deciding what is input and what is computed. Names, dates, quantities, and prices are inputs. Totals, averages, and counts are rules. That one decision keeps the sheet honest every time you edit it.

Formulas start with a link to other cells

A simple formula such as =A1+B1 adds two cells and updates when they change. Relative references move when you copy a formula, which suits row-by-row work: one formula written for the first row can fill every row below it. Absolute references with dollar signs stay fixed, which suits a rate or a tax figure that should stay on the same cell wherever the formula travels. Choosing the wrong type is a common source of quiet errors, because the sheet still computes — just against the wrong cells.

A quick test helps: copy the formula one step and look at what it points to. If the reference moved the way you wanted, it is relative. If it stayed put, it is absolute. Do that check before you fill a whole column, not after.

A hand entering values into a Calc grid sheet

A grid sheet beside the working document, so values and the rules behind them stay in view together.

Functions and formats

Functions extend the basic arithmetic

SUM, AVERAGE, IF, VLOOKUP, and COUNTIF cover a large share of office tasks. SUM adds a range, IF tests a condition, and COUNTIF counts rows that match a rule. Learn the argument order once — the function name, then the range or value it works on, then any condition — and you can read formulas written by others instead of guessing at them. The help system explains each function with examples you can test on a copy of your sheet, which is the safest place to learn: break the copy, not the original.

Number formats are part of the data

A number formatted as currency, a percentage, or a date displays differently but may hold the same value underneath. Dates are a special case because Calc stores them as numbers with a date format. Text that looks like a date will not sort or subtract correctly, and a currency figure stored as text will not add up. Set the format first, then enter the value, and the sheet behaves the way it looks.

When a total looks right but sorting or charting misbehaves, check the format before you check the formula. The number is often there; it is simply stored in the wrong form.

A printed table sheet beside filed records

Keeping each record on one row is what makes sorting and filtering safe.

Sorting, filters, and flags

Sorting must respect your row structure

Sort a full data range, including every column that belongs to a record. Sorting one column alone breaks the link between a name and its amount, and the damage is hard to spot because every value still looks plausible. Add a header row so Calc knows the first row holds labels, and test a sort on a copy when the sheet matters.

Filters answer questions without changing data

AutoFilter lets you show rows that meet a condition while leaving the sheet intact. You can isolate one month, one category, or one supplier for a quick total, then clear the filter when you finish so the next person sees the full list. Filters are a view, not a new file.

Conditional formatting highlights what needs attention

Conditional formatting changes cell appearance when a value meets a rule you set. It can flag overdue dates, negative balances, or stock below a threshold. The underlying value stays the same, which keeps the sheet honest. Too many colours, however, make the flag useless, so keep one or two rules per sheet and make each one mean something you would act on.

Hands filing printed templates into a desk drawer

Presenting the sheet

Charts should answer one question

A chart in Calc summarises a range you select, such as monthly spend by category. Choose a chart type that matches the question, with bars for comparison and lines for trend. Label axes and units so a reader does not need your explanation. Update the source range rather than retyping chart data, so the chart and the sheet can never drift apart.

If a reader asks what the chart is about after looking at it, the labels are doing too little. One question, one chart, and a title that states the answer.

Print setup is often skipped and then regretted

Set print ranges, page orientation, and repeating header rows before the deadline. Check that column widths fit the page and that gridlines appear only when you want them. A one page summary for a meeting is different from a full data dump. Preview the printed result in Calc first, while there is still time to fix it.

Pivot-style summaries keep small data readable

For a list with categories, a summary table that groups and totals rows is easier to read than raw data. DataPilot in Calc builds that kind of summary from a selected range. Keep the source data unchanged and build the summary beside it. Label the summary so nobody mistakes it for source data, and update it from the range rather than by hand.

Both habits share the same principle as everything above: the sheet stays the source of truth, and everything else — charts, summaries, printouts — is built from it.

Help and safe edits

Keep a clean copy before risky edits

Save a copy before you sort, filter, or replace values across a large range. Work on the copy, check totals, then replace the original only when the result is right. That habit turns a risky edit into a reversible one. It costs one file and saves a rebuild.

Read the Microsoft Office compatibility guide Read the styles and templates guide Read the LibreOffice Base guide

Calc help is organised around the app

Calc Help sits apart from Writer Help and Impress Help in the online system, so search within Calc help rather than the whole suite. Search for the function or dialog name exactly as it appears on screen. Press F1 for built-in help when it is installed. The 2026 help pages reflect current menu wording for recent branches, which matters when you follow a guide written against an older version.

Help sheets filed in a walnut desk drawer

Questions people ask

What is the difference between a relative and an absolute reference?

A relative reference moves when a formula is copied, while an absolute reference stays fixed on one cell. Use absolute references for rates and constants that should not shift.

Why does a Calc date sort badly?

The value may be stored as text rather than a date number. Format the cells as dates, re-enter the values, and check sorting again on a copy.

Next sheet on the desk

Take the sheet with you

When the Calc sheet works, the next jobs follow naturally: keeping the same document readable in Microsoft Office, reusing its look through styles and templates, or moving a long list into Base where it belongs. Start with the one that matches the task waiting for you.

Microsoft Office compatibility Back to all guides

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