OCR vs MICR: the differences, and where each fits in check processing

OCR (optical character recognition) reads printed or handwritten text from an image of any document by recognizing the shapes of characters. MICR (magnetic ink character recognition) reads one specific thing: the line of magnetic-ink characters printed along the bottom of a check, which carries the routing number, account number and check number. OCR is general purpose; MICR is a banking standard built for fast, reliable check handling, and in modern check processing the two work together.

Below: how each works, a side-by-side comparison, the devices that read MICR, and how the two combine in image-based check processing.

What is OCR?

OCR converts images of text, such as scans, photos and image-only PDFs, into machine-readable text. Modern engines use neural networks that read whole lines, many fonts and languages, and often handwriting, on almost any document: bank statements, invoices, forms, IDs and checks.

OCR on its own returns text. To pull specific fields, such as the amount on a check or the payee's name, it's combined with document AI that knows where those fields are and what they mean. For more, see what OCR is and IDP vs OCR.

What is MICR?

MICR is the technology banks use to read the code line at the bottom of checks. The characters are printed in magnetic ink, so a reader can detect each character's magnetic signal as well as its shape. That makes the line hard to misread, even with stamps, signatures or marks over it.

US checks use the E-13B font, which has 10 digits and 4 special symbols (transit, on-us, amount and dash). From left to right, the MICR line typically holds four fields:

• Routing number

  9 digits between two transit symbols, identifying the paying bank.

• Account number

  The customer's account at that bank, followed by the on-us symbol.

• Check number

  The serial number of the check.

• Amount

  Added by the bank of first deposit when the check is processed.

The placement, font, dimensions and magnetic signal level are specified in the ANSI X9.100-160 family of standards. Many countries in Europe and Latin America use a different MICR font, CMC-7.

MICR devices: readers, reader-sorters and scanners

A MICR device is an input device that reads the magnetic-ink line and passes it to a computer as data. Reader-sorters read and sort thousands of checks for clearing; check scanners at branches, lockboxes and businesses read the MICR line and capture the check image; MICR printers use magnetic toner to print the line on new checks.

OCR vs MICR: key differences

OCR trades MICR's reliability on one fixed line for the ability to read everything else on the check and the documents that come with it.

Where OCR and MICR are used

OCR reads documents across the business: bank statements, pay stubs and tax returns in lending; invoice fields and line items in accounts payable; ACORD forms, claims and certificates in insurance; intake forms and claims in healthcare; and everything on a check that isn't in the MICR line.

MICR has a narrower job, all of it around the check itself.

• Check clearing

  Reader-sorters use the MICR line to route each check to the paying bank and post it to the right account.

• Encoding

  The bank of first deposit adds the amount to the MICR line.

• Check printing

  Banks and businesses printing their own checks must meet the MICR standard so checks can be processed.

• Integrity checks

  A missing or faulty magnetic signal, or a MICR line that doesn't match the bank's records, is a warning sign.

How OCR and MICR work together today

Check processing has moved from paper to images. The Check Clearing for the 21st Century Act (Check 21), in effect since October 2004, made a properly prepared substitute check, a paper reproduction of the image, the legal equivalent of the original. That paved the way for banks to clear checks electronically as images.

Once a check is an image, both technologies play a part. Branch and lockbox scanners often read the MICR line magnetically and optically at once, and compare the two reads. Remote deposit capture and mobile deposit read the MICR line optically from the photo, since there's no magnetic reader. OCR and document AI read the rest: payee, date, the courtesy amount (in numbers) and legal amount (in words), memo, endorsement and any remittance advice or invoice that came with the check.

Checks are in decline but far from gone. The Federal Reserve's 2025 payments study, published in July 2026, found check payments kept falling by both number and value, and the Kansas City Fed reports that checks' share of the number of business-to-business payments fell from 32% in 2015 to 13% in 2024. The remaining volume still needs processing.

Checks to run on every scanned check

• The two amounts agreeThe courtesy amount in numbers matches the legal amount in words.
• The MICR reads agreeWhere both are available, the magnetic and optical reads of the code line match.
• The account is knownThe routing and account numbers match the bank's or your customer records.
• It's endorsed and datedThe endorsement is present and the date is valid and not stale.
• The remittance ties outThe check amount matches the invoices it pays, so it posts to the right open items.

How to automate check processing

Most teams already have the MICR side covered by their scanners or remote deposit capture. The manual work is in the rest: keying payees and amounts, matching remittance advice to open invoices, and chasing mismatches.

Docsumo reads checks and the remittance documents that come with them. Fields it's unsure about go to a reviewer, and checking a check against its remittance is a cross-document check on the Enterprise plan. It doesn't replace the MICR reader in your scanners. See check processing, IDP for financial services or our guide to OCR for checks.

• 99%99%field-level accuracy across 250+ document types
• 95%+95%+of documents processed straight through, without manual review

The bottom line

MICR is a narrow, reliable standard for the code line on checks. OCR is the general technology for reading everything else. In modern image-based check processing, they're used together: MICR identifies the check, and OCR with document AI reads what's written on it and what came with it.

Book a demo with a sample of your own checks and remittances, or start a free trial.

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