If you use Google Sheets regularly and want AI built directly into your cells rather than copy-pasting between a spreadsheet and ChatGPT, two tools worth knowing about are Numerous.ai and Sheet AI. Both let you write AI-powered formulas that work like regular spreadsheet functions. Both run inside Google Sheets without requiring you to leave the app.
They take meaningfully different approaches though, and which one works better depends on what you’re actually trying to do. Here’s an honest look at both.
What These Tools Actually Do
The core idea behind both tools is the same: instead of exporting data, running it through ChatGPT, and pasting results back, you use a formula directly in your spreadsheet. Type =AI("classify this text as positive, negative, or neutral", A1) and the cell returns the classification. The formula references your cell data, the tool sends it to an AI model, and the result appears in the sheet — just like a regular formula.
This matters because it means AI operations become part of your spreadsheet logic. You can use AI output in other formulas, filter by it, sort by it, and refresh it when your source data changes. It’s a meaningfully different workflow from the manual copy-paste approach most people default to.
| Feature | Numerous.ai | Sheet AI |
|---|---|---|
| Works in | Google Sheets (Chrome extension) | Google Sheets (add-on) |
| Core capability | AI formulas via =AI() function; bulk-fill columns with AI | ChatGPT-powered formulas and text generation in cells |
| Formula approach | Custom =AI() and =EXTRACT() functions that run in cells | =SHEETAI_BRAIN() and similar functions; also a sidebar for single-cell generation |
| Bulk processing | ✅ Strong — designed for processing entire columns at once | ⚠️ Possible but less fluid; better suited for individual cells or small batches |
| Prompt complexity | Supports multi-step and conditional prompts within formulas | Simpler prompts work best; complex instructions can be less reliable |
| Data extraction | ✅ =EXTRACT() specifically designed for pulling structured data from text | ⚠️ Possible via prompting, not a dedicated extraction function |
| Underlying model | GPT-4o and others depending on plan | GPT-3.5 / GPT-4 depending on plan |
| Pricing model | Credit-based; free tier available | Subscription-based; free tier available |
Numerous.ai: Built for Column-Level Processing
Numerous.ai’s design is optimised for bulk operations — processing an entire column of data with the same AI instruction. The core functions are =AI() for general text generation and classification, and =EXTRACT() for pulling structured data out of unstructured text. You write a prompt once, apply it to a column, and the results populate automatically.
The =EXTRACT() function is particularly useful for common business tasks: extracting company names from email addresses, pulling specific fields from customer notes, parsing address components from a messy combined field. These are tasks that would take hours manually or require custom code, and Numerous handles them cleanly via formula.
Numerous also supports more complex prompting logic — conditional instructions, multi-step processing — that works well when your AI operation has some nuance. The formula-first approach gives you the flexibility of a programming environment while staying within the spreadsheet interface.
Sheet AI: More Approachable, More Sidebar-Oriented
Sheet AI takes a slightly more approachable route for people less familiar with building AI formula syntax from scratch. It offers both formula functions (=SHEETAI_BRAIN() for text generation being the primary one) and a sidebar interface where you describe what you want and generate content for individual cells without writing a formula.
For straightforward content generation tasks — writing product descriptions based on attributes in adjacent cells, generating email subject lines from campaign details, creating summaries from data rows — Sheet AI is quick to pick up. The sidebar workflow in particular makes it accessible to people who are comfortable in Sheets but haven’t written custom function formulas before.
Where Sheet AI is less strong is bulk processing at scale. It works for individual cells and moderate-sized datasets but is less fluid than Numerous when you’re processing thousands of rows or need the AI results to be dynamically linked to changing source data.
🎯 Which Tool Fits Your Situation?
Accuracy and Reliability
Both tools depend on the quality of your prompts, and both will occasionally produce wrong or inconsistent results. The important habit with either tool is to review a sample of outputs before treating AI-generated values as ground truth — especially for classification tasks where an incorrect label could cause downstream problems.
For high-stakes decisions, treat AI formula output as a first pass to be reviewed rather than a final answer. Both tools are genuinely useful for speeding up work that would otherwise be manual; neither is a substitute for verification on anything that matters.
Common Use Cases for AI Spreadsheet Formulas
Understanding the practical use cases helps you judge which tool fits your actual work. Sentiment classification is one of the most common — feeding customer feedback, support tickets, or survey responses into an AI formula that tags each one as positive, negative, or neutral, then aggregating the results. With either tool, this turns a manual tagging job into a column formula that processes hundreds of rows automatically.
Data extraction is another strong fit: pulling a company name from a messy “Company / Contact” field, extracting the numeric value from a text string like “approximately 45 units”, or identifying the key topic from a freeform comment. These are tasks that are tedious to do manually and difficult to solve with standard text formulas, but straightforward to prompt an AI to handle.
Content generation in bulk — writing a short product description for each row based on attributes in adjacent columns, generating personalised email subject lines from CRM data, creating category tags from product names — is where both tools deliver clear time savings over any manual approach. The quality of the output varies with the quality of the prompt and the source data, but for first-draft content generation at scale, AI spreadsheet formulas are genuinely useful.
Limitations Worth Knowing
Both tools process your data via external AI APIs, which means your spreadsheet data leaves your environment when a formula runs. For public or non-sensitive data, this is generally fine. For data containing customer personal information, financial details, or anything covered by a confidentiality agreement, check the relevant data handling policies before using either tool.
Formula refresh behaviour is also worth understanding. AI formulas don’t auto-recalculate on every spreadsheet open the way standard formulas do — both tools give you control over when formulas re-run, which prevents unexpected API calls. This means you need to consciously trigger a refresh when you want updated results, which is usually the right behaviour for an AI operation that has a cost per call, but can be surprising if you expect the results to update automatically.
Pricing and Credits
Both tools charge based on API usage. With Numerous.ai, you purchase credits that are consumed as formulas run — a single cell operation costs a fraction of a credit, so a column of 500 rows might use a few dollars of credits. Sheet AI uses a subscription model with a monthly allowance of operations. In both cases, the free tier is generous enough to evaluate the tool meaningfully on your actual use cases before committing to a paid plan. For high-volume operations, estimate your expected monthly call volume against the pricing tiers before choosing a plan — the economics vary significantly depending on how many rows you process regularly.
Practical Starting Point
Both tools have free tiers that give you enough credits to evaluate whether the approach works for your specific use cases. The most useful test: take your single most repetitive data transformation task — the thing you currently do manually for each row — and try building a formula for it in each tool. The one that handles your actual task more reliably is the right choice, regardless of which has the better feature list on paper.
If you’re not sure which to start with: Sheet AI’s sidebar is the gentler introduction. If you’re comfortable with spreadsheet formulas and want more power, Numerous.ai’s formula-centric approach will feel more natural and scale better.