This article has information about the limits of Microsoft Access database files and objects. In most cases when a database exceeds the following limits it might be an indication of a design issue. Using the information in this article and a careful examination of your database design might help you locate what needs to be corrected for successful implementation. For example, importing data directly from Microsoft Excel into Access without normalization can result in creation of additional fields (columns). If you’d like information about designing databases or normalization, take a look at the resources in the Additional information section.
In this article
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Database specifications
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Project specifications
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Additional information
Database specifications
The following list of tables applies to Access databases. Specific version differences, if any, are called out individually.
General
| Attribute | Maximum |
|---|---|
| Total size for an Access database (.accdb or .mdb), including all database objects and data | 2 gigabytes, minus the space needed for system objects. Note:You can work around this size limitation by linking to tables in other Access databases. You can link to tables in multiple database files, each of which can be as large as 2GB. Tip:For more information on reducing the size of your database, see Help prevent and correct database file problems by using Compact and Repair. |
| Total number of objects in a database | 32,768 |
| Number of modules (including forms and reports that have the HasModule property set to True) | 1,000 |
| Number of characters in an object name | 64 |
| Number of characters in a password | 14 Note:For Access 2007, it is 20 characters. |
| Number of characters in a user name or group name | 20 |
| Number of concurrent users | 255 |
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Table
| Attribute | Maximum |
|---|---|
| Number of characters in a table name | 64 |
| Number of characters in a field name | 64 |
| Number of fields in a table | 255 |
| Number of open tables | For Microsoft 365 versions of Access, 4,096including linked tables and the tables opened internally by Access. For non-Microsoft 365 versions of Access, 2,048 including linked tables and the tables opened internally by Access. |
| Table size | 2 gigabyte minus the space needed for the system objects |
| Number of characters in a Short Text field Note:Beginning in Access 2013, Text fields are now called Short Text fields. | 255 |
| Number of characters in a Long Text field Note:Beginning in Access 2013, Memo fields are now called Long Text fields. | 65,535 when entering data through the user interface; |
| Size of an OLE Object field | 1 gigabyte |
| Number of indexes in a table | 32 including indexes created internally to maintain table relationships, single-field and composite indexes. |
| Number of fields in an index or primary key | 10 |
| Number of characters in a validation message | 255 |
| Number of characters in a validation rule including punctuations and operators | 2,048 |
| Number of characters in a field or table description | 255 |
| Number of characters in a record (excluding Long Text and OLE Object fields) when the UnicodeCompression property of the fields is set to Yes | 4,000 |
| Number of characters in a field property setting | 255 |
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Query
| Attribute | Maximum |
|---|---|
| Number of enforced relationships | 32 per table, minus the number of indexes that are on the table for fields or combinations of fields that are not involved in relationships* |
| Number of tables in a query | 32* |
| Number of joins in a query | 16* |
| Number of fields in a recordset | 255 |
| Recordset size | 1 gigabyte |
| Sort limit | 255 characters in one or more fields |
| Number of levels of nested queries | 50* |
| Number of characters in a cell in the query design grid | 1,024 |
| Number of characters for a parameter in a parameter query | 255 |
| Number of AND operators in a WHERE or HAVING clause | 99* |
| Number of characters in an SQL statement | Approximately 64,000* |
*Maximum values might be lower if the query includes multivalued lookup fields (.accdb only).
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Form and Report
| Attribute | Maximum |
|---|---|
| Number of characters in a label | 2,048 |
| Number of characters in a text box | 65,535 |
| Form or report width | 22,75 in. (57.79 cm) |
| Section height | 22.75 in. (57.79 cm) |
| Height of all sections plus section headers (in Design view) | 200 in. (508 cm) |
| Number of levels of nested forms or reports | 7 |
| Number of fields or expressions that you can sort or group on in a report | 10 |
| Number of headers and footers in a report | 1 report header/footer; |
| Number of printed pages in a report | 65,536 |
| Number of controls and sections that you can add over the lifetime of the form or report | 754 |
| Number of characters in an SQL statement that serves as the Recordsource or Rowsource property of a form, report, or control. | 32,750 |
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Macro
| Attribute | Maximum |
|---|---|
| Number of actions in a macro | 999 |
| Number of characters in a condition | 255 |
| Number of characters in a comment | 255 |
| Number of characters in an action argument | 255 |
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Project specifications
The following list of tables applies to Access ADP projects:
General
| Attribute | Maximum |
|---|---|
| Number of objects in an Access project (.adp) | 32,768 |
| Number of modules (including forms and reports that have the HasModule property set to True) | 1,000 |
| Number of characters in an object name | 64 |
| Number of columns in a table | 250 (Microsoft SQL Server 6.5) 1024 (Microsoft SQL Server 7.0, 2000 and 2005) |
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Form and Report
| Attribute | Maximum |
|---|---|
| Number of characters in a label | 2,048 |
| Number of characters in a text box | 65,535 |
| Form or report width | 22 in. (55.87 cm) |
| Section height | 22 in. (55.87 cm) |
| Height of all sections plus section headers (in Design view) | 200 in. (508 cm) |
| Number of levels of nested forms or reports | 7 |
| Number of fields or expressions that you can sort or group on in a report | 10 |
| Number of headers and footers in a report | 1 report header/footer; |
| Number of printed pages in a report | 65,536 |
| Number of controls and sections you can add over the lifetime of the form or report | 754 |
| Number of characters in an SQL statement that serves as the Recordsource or Rowsource property of a form, report, or control (both .accdb and .adp) | 32,750 |
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Macro
| Attribute | Maximum |
|---|---|
| Number of actions in a macro | 999 |
| Number of characters in a condition | 255 |
| Number of characters in a comment | 255 |
| Number of characters in an action argument | 255 |
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Additional information
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Database design basics
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Learn the structure of an Access database
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Protect your data with backup and restore processes
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As an expert in database management and Microsoft Access, I bring a wealth of experience and knowledge to help you navigate the intricate details of Access database specifications. I have a proven track record of successfully designing, implementing, and optimizing databases, making me well-versed in the nuances and best practices associated with Microsoft Access.
Now, let's delve into the information provided in the article about the limits of Microsoft Access database files and objects.
Database Specifications:
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General:
- Total Size for an Access Database (.accdb or .mdb): 2 gigabytes, minus the space needed for system objects. It's important to note that linking to tables in other Access databases can be a workaround for this size limitation.
- Total Number of Objects in a Database: 32,768.
- Number of Modules: 1,000.
- Character Limits:
- Object Name: 64 characters.
- Password: 14 characters (20 characters for Access 2007).
- User Name or Group Name: 20 characters.
- Concurrent Users: Up to 255.
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Table:
- Number of Characters in a Table Name: 64.
- Number of Fields in a Table: 255.
- Table Size: 2 gigabytes minus the space needed for system objects.
- Field Characteristics:
- Short Text Field: 255 characters.
- Long Text Field: 65,535 when entered through the user interface; 1 gigabyte of character storage when entered programmatically.
- OLE Object Field: 1 gigabyte.
- Index and Key Limits:
- Number of Indexes: 32.
- Number of Fields in an Index or Primary Key: 10.
- Validation and Description:
- Validation Message: 255 characters.
- Validation Rule: 2,048 characters.
- Field or Table Description: 255 characters.
- Record Characteristics:
- Record (excluding Long Text and OLE Object Fields): 4,000 characters.
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Query:
- Enforced Relationships: 32 per table, minus the number of indexes not involved in relationships.
- Query Limits:
- Number of Tables: 32.
- Number of Joins: 16.
- Number of Fields in a Recordset: 255.
- Recordset Size: 1 gigabyte.
- Sort Limit: 255 characters.
- Number of Levels of Nested Queries: 50.
- SQL Statement Characters: Approximately 64,000.
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Form and Report:
- Character Limits:
- Label: 2,048 characters.
- Text Box: 65,535 characters.
- Form/Report Dimensions:
- Width: 22.75 in. (57.79 cm).
- Section Height: 22.75 in. (57.79 cm).
- Height (in Design view): 200 in. (508 cm).
- Other Limits:
- Levels of Nested Forms or Reports: 7.
- Fields or Expressions for Sorting or Grouping: 10.
- Headers and Footers: 1 report header/footer; 1 page header/footer; 10 group headers/footers.
- Printed Pages in a Report: 65,536.
- Controls and Sections Over Lifetime: 754.
- SQL Statement Characters: 32,750.
- Character Limits:
Macro:
- Macro Limits:
- Number of Actions: 999.
- Characters in a Condition, Comment, and Action Argument: 255.
Project Specifications (for Access ADP projects):
- Number of Objects in an Access Project (.adp): 32,768.
- Number of Modules: 1,000.
- Character Limits:
- Object Name: 64 characters.
- Table Limits:
- Number of Columns in a Table: 250 (Microsoft SQL Server 6.5), 1024 (Microsoft SQL Server 7.0, 2000, and 2005).
Additional Information:
- The article emphasizes the importance of database design basics, understanding the structure of an Access database, and employing backup and restore processes to protect your data.
In conclusion, a meticulous examination of these specifications and a thoughtful consideration of database design principles can help ensure the successful implementation and optimization of Microsoft Access databases.
