# Time Series Forecast & Seasonality Analyzer Forecast future periods from CSV or JSON time-series data and inspect trend, seasonal, and residual decomposition in one report > Canonical page: https://elysiatools.com/en/tools/time-series-forecast-seasonality-analyzer - **Category:** Data Analysis - **Keywords:** time series, forecast, seasonality, trend, arima, exponential smoothing ## Overview Import CSV, JSON, or spreadsheet time-series data with a timestamp column and a numeric value column. The tool fits one of three lightweight forecasting models, projects future periods with confidence bands, and decomposes the observed series into trend, seasonal, and residual components. Model notes: - ARIMA uses a lightweight ARIMA(1,1,0)-style approximation that is practical for browser-side forecasting - Exponential smoothing uses a Holt-style level and trend update - Linear trend uses regression over the observed index plus seasonal adjustment How to fill the form: - CSV or JSON Input: paste a table or JSON array of objects - Data File: upload CSV, JSON, XLS, or XLSX instead of pasting - Timestamp Column / Value Column: choose the field names to analyze - Forecast Model: select the forecasting approach to use - Forecast Periods: number of future rows to generate - Season Length: cycle length used for decomposition and seasonal adjustment - Confidence Level: controls the forecast interval width - Export Format: preview the generated forecast rows as JSON or CSV ## Inputs - **CSV or JSON Input** (textarea): timestamp,value 2026-01-01,120 2026-01-02,123 - **Data File** (file) - **Timestamp Column** (text): timestamp - **Value Column** (text): value - **Forecast Model** (select) - **Forecast Periods** (number) - **Season Length** (number) - **Confidence Level** (select) - **Export Format** (select) ## When to use - When you need to project future metrics like sales, traffic, or inventory levels based on historical time-series data. - When you want to isolate and analyze the underlying trend and seasonal patterns within a dataset. - When you require a quick, browser-based forecasting tool without writing complex Python or R scripts. ## How it works - Paste your time-series data as CSV or JSON, or upload a CSV, JSON, XLS, or XLSX file. - Specify the exact names of your timestamp and numeric value columns. - Select a forecasting model (ARIMA, Exponential Smoothing, or Linear Trend), set the forecast periods, and define the season length. - Generate the report to view the projected data with confidence intervals and export the forecast rows as JSON or CSV. ## Use cases - Retail managers forecasting weekly sales volume while accounting for recurring weekend spikes. - Marketing analysts projecting future website traffic trends and identifying seasonal dips. - Supply chain planners estimating future inventory requirements based on historical consumption rates. ## Frequently asked questions ### What forecasting models are supported? The tool supports a lightweight ARIMA(1,1,0) approximation, Holt-style Exponential Smoothing, and Linear Trend regression with seasonal adjustment. ### What file formats can I upload? You can upload CSV, JSON, XLS, and XLSX files, or paste raw CSV and JSON text directly into the input field. ### How does the season length parameter work? The season length defines the cycle length (e.g., 7 for weekly patterns in daily data) used to calculate seasonal adjustments and decompose the series. ### Can I adjust the confidence intervals for the forecast? Yes, you can select a confidence level of 80%, 90%, 95%, or 99% to control the width of the forecast bands. ### How do I export the forecasted data? You can choose to preview and export the generated forecast rows in either JSON or CSV format using the Export Format dropdown. ## Related tools - [Time Series Anomaly Detector](https://elysiatools.com/en/tools/time-series-anomaly-detector): Upload CSV or JSON time series data, detect anomalies with Z-Score and IQR methods, and return a chart-backed report - [JSON-LD Generator from CSV](https://elysiatools.com/en/tools/json-ld-generator-from-csv): Turn CSV or Excel rows into Schema.org JSON-LD for articles, products, or events, with validation-ready output for SEO workflows - [XLSX Multi Sheet Splitter](https://elysiatools.com/en/tools/xlsx-multi-sheet-splitter): Split a multi-sheet workbook into independent files by sheet name, with ZIP output - [XLSX CSV Batch Converter](https://elysiatools.com/en/tools/xlsx-csv-batch-converter): Batch convert CSV/TSV to XLSX or convert XLSX back to CSV/TSV with delimiter and encoding handling - [XLSX Print Setup Pack](https://elysiatools.com/en/tools/xlsx-print-setup-pack): Apply paper, margins, scaling, repeating titles, and header/footer print settings to Excel workbooks in one pass - [CSV / Excel Diff Tool](https://elysiatools.com/en/tools/csv-excel-diff-tool): Compare two CSV or XLSX datasets and export a PDF report with row, column, and cell-level differences - [Text to Excel Converter](https://elysiatools.com/en/tools/text-to-excel): Convert various text formats to Excel with customizable parsing and formatting options - [Excel to CSV Converter](https://elysiatools.com/en/tools/excel-to-csv): Convert Excel file to CSV format, extracting data from the first worksheet ## Samples - [XLS Samples](https://elysiatools.com/en/samples/xls-samples): Sample legacy Excel (XLS) files for binary spreadsheet parsing and import tests - [XLSX Samples](https://elysiatools.com/en/samples/xlsx-samples): Sample XLSX spreadsheets for worksheet parsing and data extraction testing - [CSV Samples](https://elysiatools.com/en/samples/csv-samples): Sample CSV files with various data types, sizes, and complexity levels - [Python Samples](https://elysiatools.com/en/samples/python): Essential Python code examples and Hello World demonstrations ## Related content - [JSON Interchange and Format Translation Tools](https://elysiatools.com/en/hubs/json-convert): Compare JSON conversion tools for CSV, YAML, TOML, GraphQL, XML, Markdown, Excel, BSON, EDN, and related structured formats in one hub. - [Text Case, Encoding, and Normalization Conversion Tools](https://elysiatools.com/en/hubs/text-convert): Compare text case conversion, character-width conversion, encoding conversion, quoted-printable handling, and inline text normalization tools in one hub. - [CSV Export and Table Conversion Tools](https://elysiatools.com/en/hubs/csv-convert): Compare CSV to Excel, JSON, HTML, Markdown, XML, and text conversion tools in one hub for tabular export and interchange workflows. - [XML Conversion, Mapping, and XPath Tools](https://elysiatools.com/en/hubs/xml-convert): Curated tools for XML conversion, mapping, merging, and XPath extraction in one hub.