National Highway Traffic Safety Administration (NHTSA)
948,611Words in 84 parts
10.7Restriction density (per 1,000 words)
16.0Reading grade
62.9%Unchanged since 2017
6Flagged parts
2026-10-09Last change
Section changes per year
From the eCFR versioner, for the parts that the agency owns now. Before 2017 is the baseline load.
Text and size
- Sentences
- 28.9 words on average; 22.2% over 40 words; 29.1% passive; 8.3 cross-references per 1,000 words
- Sentence types
- definition 6.4% · prohibition 2.8% · paperwork 3.9% · obligation 18.6% · permission 5.1% · other 63.2%
- Checksum
b7e4e54c55ee116b4ee756ac37f81d10631ef673077aa19ccaca9e9754834e67
Review candidates in this agency
| Rank | Part | Words | Score |
|---|---|---|---|
| 36 top 10% | 49 CFR 577
DEFECT AND NONCOMPLIANCE NOTIFICATION
High signals: Paperwork share
+2.9 SD · Directive share
+1.8 SD · Reading grade
+1.6 SD · Restriction density
+1.5 SD |
6,807 | 1.45 |
| 57 top 10% | 49 CFR 591
IMPORTATION OF VEHICLES AND EQUIPMENT SUBJECT TO FEDERAL SAFETY, BUMPER AND THEFT PREVENTION STANDARDS
High signals: Reading grade
+4.9 SD · Directive share
+1.4 SD |
8,379 | 1.31 |
| 61 top 10% | 49 CFR 573
DEFECT AND NONCOMPLIANCE RESPONSIBILITY AND REPORTS
High signals: Paperwork share
+2.3 SD · Directive share
+1.8 SD · Reading grade
+1.5 SD |
9,878 | 1.29 |
| 98 top 10% | 49 CFR 592
REGISTERED IMPORTERS OF VEHICLES NOT ORIGINALLY MANUFACTURED TO CONFORM TO THE FEDERAL MOTOR VEHICLE SAFETY STANDARDS
High signals: Paperwork share
+2.3 SD · Reading grade
+1.9 SD · Directive share
+1.2 SD |
9,450 | 1.16 |
| 174 top 10% | 49 CFR 537
AUTOMOTIVE FUEL ECONOMY REPORTS
High signals: Paperwork share
+3.6 SD · Restriction density
+1.6 SD · Directive share
+1.5 SD |
5,628 | 1.03 |
| 213 top 10% | 49 CFR 579
REPORTING OF INFORMATION AND COMMUNICATIONS ABOUT POTENTIAL DEFECTS
High signals: Paperwork share
+2.6 SD · Reading grade
+1.0 SD |
17,797 | 0.97 |
| 754 | 49 CFR 580
ODOMETER DISCLOSURE REQUIREMENTS
High signals: Paperwork share
+2.4 SD |
7,794 | 0.66 |
| 809 | 23 CFR 1327
PROCEDURES FOR PARTICIPATING IN AND RECEIVING INFORMATION FROM THE NATIONAL DRIVER REGISTER PROBLEM DRIVER POINTER SYSTEM
High signals: Reading grade
+2.5 SD · Paperwork share
+2.3 SD |
8,366 | 0.63 |
| 858 | 49 CFR 511
ADJUDICATIVE PROCEDURES
High signals: Restriction density
+1.7 SD |
16,788 | 0.61 |
| 1,013 | 49 CFR 555
TEMPORARY EXEMPTION FROM MOTOR VEHICLE SAFETY AND BUMPER STANDARDS
High signals: Reading grade
+1.7 SD · Paperwork share
+1.6 SD |
4,306 | 0.55 |
| 1,546 | 49 CFR 583
AUTOMOBILE PARTS CONTENT LABELING
High signals: none above 1 SD; ranked by the combined score |
7,383 | 0.40 |
| 1,602 | 23 CFR 1235
UNIFORM SYSTEM FOR PARKING FOR PERSONS WITH DISABILITIES
High signals: Paperwork share
+2.0 SD · Directive share
+1.7 SD · Restriction density
+1.5 SD |
1,331 | 0.39 |
| 1,791 | 49 CFR 574
TIRE IDENTIFICATION AND RECORDKEEPING
High signals: Paperwork share
+1.1 SD |
5,025 | 0.33 |
| 1,912 | 49 CFR 526
PETITIONS AND PLANS FOR RELIEF UNDER THE AUTOMOBILE FUEL EFFICIENCY ACT OF 1980
High signals: Reading grade
+1.6 SD · Paperwork share
+1.0 SD |
1,002 | 0.30 |
| 1,914 | 23 CFR 1300
UNIFORM PROCEDURES FOR STATE HIGHWAY SAFETY GRANT PROGRAMS
High signals: Size
+1.5 SD · Reading grade
+1.2 SD |
32,599 | 0.30 |
| 1,942 | 49 CFR 529
MANUFACTURERS OF MULTISTAGE AUTOMOBILES
High signals: Reading grade
+1.6 SD |
2,106 | 0.29 |
| 1,968 | 49 CFR 567
CERTIFICATION
High signals: none above 1 SD; ranked by the combined score |
5,687 | 0.28 |
| 1,974 | 49 CFR 565
VEHICLE IDENTIFICATION NUMBER (VIN) REQUIREMENTS
High signals: Directive share
+1.3 SD |
6,869 | 0.28 |
| 2,123 | 49 CFR 545
FEDERAL MOTOR VEHICLE THEFT PREVENTION STANDARD PHASE-IN AND SMALL-VOLUME LINE REPORTING REQUIREMENTS
High signals: Paperwork share
+2.0 SD |
1,028 | 0.24 |
| 2,211 | 49 CFR 512
CONFIDENTIAL BUSINESS INFORMATION
High signals: none above 1 SD; ranked by the combined score |
5,157 | 0.23 |
| 2,448 | 23 CFR 1200
UNIFORM PROCEDURES FOR STATE HIGHWAY SAFETY GRANT PROGRAMS
High signals: Size
+1.3 SD |
26,089 | 0.17 |
| 2,526 | 49 CFR 551
PROCEDURAL RULES
High signals: Restriction density
+1.4 SD |
2,377 | 0.15 |
| 2,725 | 49 CFR 595
MAKE INOPERATIVE EXEMPTIONS
High signals: none above 1 SD; ranked by the combined score |
3,893 | 0.10 |
| 2,916 | 49 CFR 571
FEDERAL MOTOR VEHICLE SAFETY STANDARDS
High signals: Size
+3.8 SD |
502,835 | 0.06 |
| 2,919 | 23 CFR 1225
OPERATION OF MOTOR VEHICLES BY INTOXICATED PERSONS
High signals: Paperwork share
+1.5 SD |
3,095 | 0.05 |
Score: the mean of six signals, in standard deviations (SD). Across the CFR, the top 641 of 6,402 ranked parts (10%) get a flag for review; this list shows 25. A flag is not a finding.
Statutes behind the most text
- 49 U.S.C. 322: 654,715 words in 23 parts (69.0% of this agency's text)
- 23 U.S.C. 402: 61,820 words in 3 parts (6.5% of this agency's text)
- 23 U.S.C. 405: 58,688 words in 2 parts (6.2% of this agency's text)
- 49 U.S.C. 32902: 45,562 words in 3 parts (4.8% of this agency's text)
- 49 U.S.C. 30102: 35,551 words in 4 parts (3.7% of this agency's text)
- 15 U.S.C. 1232: 26,989 words in 1 parts (2.8% of this agency's text)
- 49 U.S.C. 32302: 26,989 words in 1 parts (2.8% of this agency's text)
- 15 U.S.C. 2002: 20,187 words in 3 parts (2.1% of this agency's text)
- 49 U.S.C. 30301: 8,366 words in 1 parts (0.9% of this agency's text)
- 49 U.S.C. 32705: 7,794 words in 1 parts (0.8% of this agency's text)
From the authority notes. A citation is not proof that the statute requires the rule.
Largest parts
- 49 CFR 571: FEDERAL MOTOR VEHICLE SAFETY STANDARDS (502,835 words)
- 49 CFR 572: ANTHROPOMORPHIC TEST DEVICES (65,092 words)
- 49 CFR 535: MEDIUM- AND HEAVY-DUTY VEHICLE FUEL EFFICIENCY PROGRAM (37,811 words)
- 23 CFR 1300: UNIFORM PROCEDURES FOR STATE HIGHWAY SAFETY GRANT PROGRAMS (32,599 words)
- 49 CFR 575: CONSUMER INFORMATION (26,989 words)
- 23 CFR 1200: UNIFORM PROCEDURES FOR STATE HIGHWAY SAFETY GRANT PROGRAMS (26,089 words)
- 49 CFR 579: REPORTING OF INFORMATION AND COMMUNICATIONS ABOUT POTENTIAL DEFECTS (17,797 words)
- 49 CFR 511: ADJUDICATIVE PROCEDURES (16,788 words)
- 49 CFR 573: DEFECT AND NONCOMPLIANCE RESPONSIBILITY AND REPORTS (9,878 words)
- 49 CFR 592: REGISTERED IMPORTERS OF VEHICLES NOT ORIGINALLY MANUFACTURED TO CONFORM TO THE FEDERAL MOTOR VEHICLE SAFETY STANDARDS (9,450 words)
Reading grade and sentence types are approximate. Simple rules label each sentence; the first match wins.