🔢 Sequence Number Generator
Client-side computation batch sequence generator with Simple mode (prefix+start+step+padding+suffix), DSL templates ({n:04} {ALPHA} {ROMAN} {cn} {CN} {date:YYYY-MM-DD} {rand:6}), Date mode, 9 output formats (TXT/CSV/JSON/TSV/SQL/Markdown), BigInt big-number support, fixed-point decimals, Chinese numerals & financial uppercase, Excel column letters, Roman numerals, shuffle, presets, up to 100k rows, mobile-first UI
Mode
Date options (used when template contains {date:...})
Presets
Options
Output Format
Preview
FAQ
What does each token mean in the template?
{n}= decimal counter;{n:04}= zero-padded to 4;{n:x}/{n:X}= hex;{n:o}/{n:b}= octal/binary{alpha}/{ALPHA}= Excel column letters (A..Z, AA..AZ){roman}/{ROMAN}= Roman numerals (1-3999){cn}= Chinese numerals (一二三);{CN}= Chinese financial uppercase (壹贰叁), 1-99999999{date:FMT}= date (YYYY MM DD HH mm ss tokens){rand:N}= N-digit random;{rand:hex:N}/{rand:alpha:N}{{/}}= literal { and }
How to generate invoice or date-stamped order numbers?
Switch to Advanced mode, use a template like INV-{date:YYYYMMDD}-{n:04} or click the Invoice preset. Set the base date and step unit in Date options. Default base date is today, default step is 1 day.
Does it handle very large numbers or decimal steps correctly?
Large numbers auto-promote to BigInt when exceeding 2^53. Decimal steps use fixed-point arithmetic (scale to BigInt at max precision) to avoid FP drift (0.1 + 0.2 ≠ 0.3). A badge appears below the input when promotion occurs.
What happens with month-end and leap year dates?
Month-end clamps to the target month's last day (Jan 31 + 1 month → Feb 28/29, not Mar 3). Leap year: Feb 29, 2024 + 1 year → Feb 28, 2025.
Is data uploaded? What is the max row count?
Runs in your browser — zero backend, input files are not uploaded, no login. Max 100,000 rows per generation (chunked above 10,000 to keep UI responsive, with progress bar). For larger batches, run multiple times or concatenate the downloaded CSV files.
Sequence Number Generator batch-generates invoice numbers, order IDs, SKUs, student IDs, tracking numbers, ticket numbers and other serial patterns entirely in your browser. Two modes: Simple mode composes sequences from five fields (prefix + start + step + padding width + suffix); Advanced mode uses a visual DSL template with clickable token chips ({n}, {n:04}, {ALPHA}, {ROMAN}, {cn}, {CN}, {date:YYYY-MM-DD}, {rand:6}). Built-in BigInt auto-promotion for values beyond 2^53, fixed-point arithmetic for decimal steps (avoids 0.1+0.2 drift), bijective base-26 Excel column letters (A..Z, AA..AZ), Roman numerals up to 3999, Chinese numerals in common and financial forms (一二三 / 壹贰叁), date sequences with day/week/month/year steps and month-end clamp (Jan 31 + 1 month → Feb 28/29), reproducible shuffle with optional Mulberry32 seed, up to 100,000 rows (chunked above 10,000 to keep the UI responsive). Nine output formats: plain list, comma-separated, TSV, JSON array, CSV single-column (optional header + UTF-8 BOM for Excel Chinese compatibility), SQL INSERT, Markdown bullet list, Markdown numbered list, custom separator. Seven bilingual presets fill the template with one click. Mobile-first 375px single-column layout, 44px touch targets, and token chip inserters. Client-side computation, zero dependencies, zero backend, zero login — input data is not uploaded by the tool.